Comments and Whitespace Sensitivity-1
1.
Which of the following is the correct way to add a single-line comment in
PHP?
a) # This is a single-line comment
b) // This is a single-line comment
c) /* This is a single-line comment */
d) Both a and b
Answer: d) Both a and b
2.
What is the correct syntax for a multi-line comment in PHP?
a) <!-- This is a multi-line comment -->
b) /* This is a multi-line comment */
c) # This is a multi-line comment #
d) // This is a multi-line comment
Answer: b) /* This is a multi-line comment
*/
3.
What will be the output of the following PHP code if $value is set to 10?
<?php
// Set value
$value = 10;
// Value assigned
echo $value;
?>
a) 10
b) // Set value
c) // Value assigned
d) Error
Answer: a) 10
4.
Which of the following is a valid way to use comments in PHP to make code
more readable?
a) /* This function calculates the sum of two numbers */
b) // This function calculates the sum of two numbers
c) Both a and b
d) <!-- This function calculates the sum of two numbers -->
Answer: c) Both a and b
5.
How does PHP handle whitespace in code?
a) Whitespace is ignored in PHP and does not affect code execution
b) Whitespace affects the way PHP code is executed
c) Whitespace is required between PHP statements
d) Whitespace is used to concatenate strings
Answer: a) Whitespace is ignored in PHP and
does not affect code execution
6.
What will be the result of the following PHP code due to whitespace
sensitivity?
<?php
$a = 5;
$b = 10;
$c = $a
+ $b;
echo $c;
?>
a) 15
b) 5 + 10
c) Error
d) 5
Answer: a) 15
7.
Which PHP comment style should be avoided for code that will be executed?
a) // Single-line comments
b) /* Multi-line comments */
c) <!-- HTML comments -->
d) # Single-line comments
Answer: c) <!-- HTML comments -->
8.
What will be the output of this code if $x is set to 7?
<?php
$x = 7;
// This is
the start of the code
echo $x;
/*
This is a
multi-line comment
that spans
multiple lines
*/
?>
a) 7
b) // This is the start of the code
c) /* This is a multi-line comment that spans multiple lines */
d) Error
Answer: a) 7
9.
How does PHP treat whitespace between PHP tags and statements?
a) Whitespace can be placed anywhere and does not affect the execution
b) Whitespace must be used to separate PHP tags
c) Excessive whitespace can cause syntax errors
d) Whitespace must be avoided between PHP tags and statements
Answer: a) Whitespace can be placed anywhere
and does not affect the execution
10.What is the result of this PHP code if $value is set
to 20?
<?php
$value = 20;
/* Output
value */
echo $value;
?>
a) 20
b) /* Output value */
c) Error
d) Output value
Answer: a) 20
Comments
and Whitespace Sensitivity-2
1.
Which of the following is a valid single-line comment in PHP?
a) # This is a valid comment
b) // This is a valid comment
c) /* This is not a valid comment */
d) Both a and b
Answer: d) Both a and b
2.
What happens if you use an HTML comment inside a PHP block?
<?php
/* This is a
PHP comment */
<!-- This
is an HTML comment -->
?>
a) Both
comments are ignored
b) The HTML comment is displayed as part of the output
c) The PHP comment is ignored, and the HTML comment causes an error
d) Both comments are displayed as part of the output
Answer: a) Both comments are ignored
3.
How does PHP treat whitespace at the end of a PHP statement?
a) Whitespace at the end of a statement is considered part of the statement
b) Whitespace at the end of a statement is ignored
c) Whitespace at the end of a statement causes a syntax error
d) It is required for the statement to execute correctly
Answer: b) Whitespace at the end of a
statement is ignored
4.
What will be the output of the following PHP code?
<?php
// This is a
single-line comment
$x = 5; /*
This is a multi-line comment */
echo $x;
?>
a) 5
b) // This is a single-line comment
c) /* This is a multi-line comment */
d) Error
Answer: a) 5
5.
What is the effect of whitespace within a PHP statement?
a) It can be used to improve code readability
b) It affects the code execution
c) It changes the value of variables
d) It must be avoided
Answer: a) It can be used to improve code
readability
6.
How does PHP handle the whitespace between operators and operands in
expressions?
a) Whitespace is ignored and does not affect the expression
b) Whitespace is required for correct execution
c) Excessive whitespace results in syntax errors
d) Whitespace changes the meaning of the expression
Answer: a) Whitespace is ignored and does
not affect the expression
7.
What is the result of the following PHP code due to whitespace placement?
<?php
$sum = 5
+ 10;
echo $sum;
?>
a) 15
b) 5 + 10
c) Error
d) 5
Answer: a) 15
8.
What will the following PHP code output?
<?php
/* Comment
*/
$number =
25;
echo
$number;
?>
a) 25
b) /* Comment */
c) Error
d) Comment
Answer: a) 25
9.
What is the impact of comments on PHP code execution?
a) Comments are ignored by the PHP interpreter and do not affect execution
b) Comments are executed as part of the code
c) Comments can cause syntax errors if not properly used
d) Comments are required for the code to execute
Answer: a) Comments are ignored by the PHP
interpreter and do not affect execution
10.Which of the following is true about whitespace in PHP
code?
a) PHP ignores all whitespace
b) Whitespace must be used to separate PHP tags
c) Excessive whitespace can make code harder to read but does not affect
execution
d) Whitespace is used to separate PHP from HTML
Answer: c) Excessive whitespace can make
code harder to read but does not affect execution
Comments and Whitespace Sensitivity-3
1.
Which of the following statements about comments in PHP is true?
a) Comments within PHP code are ignored during execution
b) Comments must be placed before every PHP statement
c) Comments affect the output of the PHP script
d) Comments are used to execute PHP code
Answer: a) Comments within PHP code are
ignored during execution
2.
What is the result of this PHP code if $value is set to 30?
<?php
/* Set value
*/
$value = 30;
// Output
value
echo $value;
?>
a) 30
b) /* Set value */
c) // Output value
d) Error
Answer: a) 30
3.
How does PHP treat whitespace in variable names?
a) Whitespace is allowed in variable names
b) Whitespace is not allowed in variable names
c) Whitespace can be used to concatenate variable names
d) Whitespace changes the meaning of the variable
Answer: b) Whitespace is not allowed in
variable names
4.
What will the following PHP code output if $x is set to 15?
<?php
$x = 15;
$y = $x
+ 5;
echo $y;
?>
a) 20
b) 15 + 5
c) 15
d) Error
Answer: a) 20
5.
What is the purpose of using comments in PHP code?
a) To explain and document code for future reference
b) To execute PHP code
c) To change the output of the script
d) To handle errors
Answer: a) To explain and document code for
future reference
6.
What will be the output of this PHP code if $x is set to 5 and $y is set
to 10?
<?php
$x = 5;
$y = 10;
$sum = $x
+
$y;
echo $sum;
?>
a) 15
b) 5 + 10
c) 5
d) Error
Answer: a) 15
7.
Which comment style is most appropriate for adding descriptive notes
about code functionality in PHP?
a) /* Multi-line comments */
b) // Single-line comments
c) # Single-line comments
d) All of the above
Answer: d) All of the above
8.
What will be the output of this PHP code if $text is set to "Hello
World"?
<?php
$text =
"Hello World";
echo $text;
// Output the text
?>
a) Hello
World
b) // Output the text
c) Hello World // Output the text
d) Error
Answer: a) Hello World
9.
What is the result of this PHP code when $value is 0?
<?php
$value = 0;
$result =
$value
+ 100;
echo
$result;
?>
a) 100
b) 0 + 100
c) 0
d) Error
Answer: a) 100
10.What happens if you put a PHP comment inside an HTML
tag?
<html>
<body>
<?php
// Comment
inside PHP
?>
<p>Text
here <!-- HTML comment --> </p>
</body>
</html>
a) HTML
comments are ignored by PHP and displayed as is
b) HTML comments are converted into PHP comments
c) PHP comments are displayed as part of the HTML output
d) The HTML comment causes a syntax error
Answer: a) HTML comments are ignored by PHP
and displayed as is
Comments and Whitespace Sensitivity-4
1.
How does PHP handle whitespace inside string literals?
a) Whitespace is removed from string literals
b) Whitespace is preserved exactly as it appears in the string
c) Whitespace is replaced with a default character
d) Whitespace is ignored
Answer: b) Whitespace is preserved exactly
as it appears in the string
2.
What is the output of this PHP code?
<?php
$name =
"Alice"; // Name variable
$greeting =
"Hello, $name!";
echo
$greeting;
?>
a) Hello,
Alice!
b) Hello, $name!
c) Hello, Alice; // Name variable!
d) Error
Answer: a) Hello, Alice!
3.
What does the following PHP code output?
<?php
$a = 2;
$b = 4;
$sum = $a
+ $b;
echo $sum;
?>
a) 6
b) 2 + 4
c) Error
d) 2 4
Answer: a) 6
4.
How do you add a comment in PHP that spans multiple lines?
a) /* This is a multi-line comment */
b) <!-- This is a multi-line comment -->
c) // This is a multi-line comment
d) # This is a multi-line comment
Answer: a) /* This is a multi-line comment
*/
5.
What will be the output of this PHP code if $x is set to 8?
<?php
$x = 8;
// Comment:
Displaying value
echo $x;
?>
a) 8
b) // Comment: Displaying value
c) 8 // Comment: Displaying value
d) Error
Answer: a) 8
6.
What is the result of the following code?
<?php
$a = 5;
$b = $a
+ 15;
$c = $b
+ $a;
echo $c;
?>
a) 25
b) 20
c) 5 + 15 + 5
d) Error
Answer: a) 25
7.
What is the correct way to write a single-line comment in PHP within a
block of PHP code?
a) // This is a single-line comment
b) # This is a single-line comment
c) /* This is a single-line comment */
d) Both a and b
Answer: d) Both a and b
8.
How does PHP process whitespace around PHP tags?
a) Whitespace outside of PHP tags is ignored
b) Whitespace inside PHP tags is required
c) Whitespace within PHP tags affects the execution
d) Whitespace is removed before executing PHP code
Answer: a) Whitespace outside of PHP tags is
ignored
9.
What will be the output of this code?
<?php
$x = 10;
$y = 20;
$z = $x
+
$y;
echo $z;
?>
a) 30
b) 10 + 20
c) Error
d) 10
Answer: a) 30
10.What is the effect of putting a comment inside an echo
statement in PHP?
<?php
echo
"Hello, world!"; // Comment here
?>
a) The
comment is ignored and does not affect the output
b) The comment is displayed as part of the output
c) The comment causes a syntax error
d) The comment modifies the output
Answer: a) The comment is ignored and does
not affect the output
Comments
and Whitespace Sensitivity-5
1.
What will the following PHP code output if $value is set to "Hello
"?
<?php
$value =
"Hello ";
// Add World
$value .=
"World!";
echo $value;
?>
a) Hello
World!
b) Hello
c) Hello World
d) Hello // Add World World!
Answer: a) Hello World!
2.
How does PHP handle whitespace before the closing ?> tag in a PHP
file?
a) Whitespace before the closing tag is ignored
b) Whitespace before the closing tag is included in the output
c) Whitespace before the closing tag causes an error
d) Whitespace before the closing tag must be avoided
Answer: b) Whitespace before the closing tag
is included in the output
3.
What is the effect of placing a comment inside a PHP function?
<?php
function
greet() {
// This is a comment
echo "Hello!";
}
greet();
?>
a) The
comment is ignored and does not affect the function execution
b) The comment is displayed as part of the output
c) The comment causes the function to fail
d) The comment modifies the output
Answer: a) The comment is ignored and does
not affect the function execution
4.
What will be the result of this PHP code if $total is set to 50?
<?php
$total = 50;
// Add 10
$total =
$total + 10;
echo $total;
?>
a) 60
b) 50
c) // Add 10
d) Error
Answer: a) 60
5.
Which PHP comment style can be used to add notes or explanations to code
without affecting the code execution?
a) /* This is a multi-line comment */
b) // This is a single-line comment
c) # This is a single-line comment
d) All of the above
Answer: d) All of the above
6.
What will be the output of this PHP code if $x is 5 and $y is 10?
<?php
$x = 5;
$y = 10;
$result = $x
+ $y;
echo
$result;
?>
a) 15
b) 5 + 10
c) 5
d) Error
Answer: a) 15
7.
How does PHP handle whitespace in the middle of variable names?
a) Whitespace is allowed and treated as part of the variable name
b) Whitespace is not allowed in variable names
c) Whitespace is ignored and variable names are concatenated
d) Whitespace is used to separate variable names
Answer: b) Whitespace is not allowed in
variable names
8.
What is the result of this PHP code?
<?php
$num = 7;
/*
This is a
multi-line comment
that spans
multiple lines
*/
$num = $num
+ 3;
echo $num;
?>
a) 10
b) 7 + 3
c) 7
d) Error
Answer: a) 10
9.
What will be the output of this PHP code if the comment is correctly
placed?
<?php
$x = 100;
// This is a
comment
$y = 50;
echo $x +
$y;
?>
a) 150
b) 100 + 50
c) // This is a comment
d) Error
Answer: a) 150
10.What does the following PHP code do?
<?php
$a = 5;
$b = 10;
$result = $a
+
$b;
echo
$result;
?>
a) Adds $a
and $b and outputs 15
b) Outputs 5 + 10
c) Outputs 5
d) Causes a syntax error