What will be the output of the following PHP code?
<?php
$a1 = array(“a” => “red”, “b” => “green”, “c” => “blue”, “d” => “yellow”);
$result = array_flip($a1);
print_r($result);
?>
a) Array ( [red] => red [green] => green [blue] => blue [yellow] => yellow )
b) Array ( [a] => a [b] => b [c] => c [d] => d )
c) Array ( [red] => a [green] => b [blue] => c [yellow] => d )
d) Array ( [a] => red [b] => green [c] => blue [d] => yellow )

Answer: c
Explanation: The function array_flip() flips/exchanges all keys with their associated values in an array. So, in the above program “a” will be flipped with “red”, “b” will be flipped with “green” and so on.