creating variable name by concatenating strings in php

Question

I have a file named questions.php with an array as follows :

$question12 = array("Which is the tallest mountain","Mt Everest");

I am including this file in another file as follows :

require_once('questions.php');
$var = 12;
$question = '$question'.$var.'[0]';
echo $question;

The above code just outputs the following string (not the contents of the variable):

$question12[0]

But I want the variable $question to contain the string present in $question12[0].

How do I accomplish this?

Answer 1

Variable variable is not recommended, but the answer is below:

$question = ${'question'.$var}[0];