What will be the output of the following PHP code?

$greet = function($name) {
return "Hello, $name!";
};
echo $greet("John");
?>

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

A). check_function()

B). function_exists()

C). function_check()

D). exists_function()

Which of the following statements about return types in PHP functions is true?

A). PHP functions must always have a return type

B). PHP functions can have a return type specified using the 'returns' keyword

C). PHP functions can have a return type specified using the 'return' keyword

D). PHP functions can have a return type declared using type declarations

What is the output of the following PHP code?

<?php
$num = 10;
function testScope() {
global $num;
echo $num;
}
testScope();
?>

A). 10

B). 0

C). Undefined variable: num

D). Variable $num cannot be accessed outside the function

What will be the output of the following PHP code?

<?php
function add($a, $b) {
return $a + $b;
}
$result = add(5, 3);
echo $result;
?>

A). 8

B). add(5, 3)

C). function add($a, $b) {
return $a + $b;
}

D). $a + $b

Which PHP feature allows passing a function as an argument to another function?

A). Dynamic functions

B). Global functions

C). Static functions

D). Callbacks

Which PHP keyword is used to declare a variable-length argument list in a function?

A). vararg

B). args

C). params

D). ...$args

What is the syntax for calling a function in PHP?

A). callFunction()

B). function callFunction()

C). callFunction

D). callFunction;

Which of the following statements is true about function names in PHP?

A). Function names are case-sensitive

B). Function names must start with a dollar sign ($)

C). Function names cannot contain numbers

D). Function names can contain spaces

What is the output of the following PHP code?

<?php
function multiply(...$args) {
$result = 1;
foreach ($args as $value) {
$result *= $value;
}
return $result;
}
echo multiply(2, 3, 4);
?>

A). 24

B). 9

C). 6

D). 2

What is the purpose of the return statement in PHP functions?

A). To terminate the function execution

B). To output a value from the function and terminate its execution

C). To define the function name

D). To declare a variable within the function