What is the output of the following PHP code?
function outer() {
function inner() {
echo "Inner function";
}
}
inner();
?

Which of the following statements about returning values from PHP functions is true?

A). PHP functions can return multiple values simultaneously

B). PHP functions cannot return values

C). PHP functions must always return a value

D). PHP functions can only return values of type string

What is the significance of passing functions as arguments in PHP?

A). It allows functions to be called multiple times

B). It simplifies the function definition process

C). It enables dynamic function invocation and behavior

D). It prevents code duplication

Which PHP feature allows specifying default values for function arguments?

A). Default arguments

B). Optional parameters

C). Variable-length argument lists

D). All of the above

Which PHP keyword is used to pass a function as an argument to another function?

A). Dynamic functions

B). Anonymous functions

C). Callbacks

D). All of the above

What is the purpose of passing arguments to a function in PHP?

A). To specify the return value of the function

B). To allow the function to accept input data

C). To define the function name

D). To terminate the execution of the function

Which PHP function is used to return a value from a function and terminate its execution?

A). return

B). exit

C). break

D). continue

Which keyword is used to define default parameter values in PHP functions?

A). default

B). var

C). const

D). None of the above

What will be the output of the following PHP code?
<?php
function greet() {
echo 'Hello, World!';
}
if (function_exists('greet')) {
greet();
} else {
echo 'Function does not exist';
}
?

A). Hello, World!

B). Function does not exist

C). Undefined function: greet

D). Function greet() { echo 'Hello, World!'; }

Which PHP feature allows defining functions with variable-length argument lists?

A). Dynamic functions

B). Variable arguments

C). Varargs

D). All of the above

Which PHP function is used to check if a function exists before calling it?

A). function_exists()

B). is_function()

C). function_defined()

D). None of the above