What will be the output of the following PHP code ?

Answer: Option A

Solution:

Understanding the PHP Code:
The code defines a function named 'fun' that takes two arguments, $a < / s t r o n g > an d < s t r o n g >$ b.
Inside the function:
  The value of $b is changed to 3.
  The function calculates $a -$ b + $b -$ a, which simplifies to 0 (because the $a < / s t r o n g > an d < s t r o n g > - a < / s t r o n g > c an ce l e a c h o t h er o u t, an d < s t r o n g >$ b and -b cancel each other out).
  The function then returns this result (which is 0).
Outside the function:
  The values of $a < / s t r o n g > an d < s t r o n g >$ b are initially set to 10 and 4 respectively.
  The function 'fun' is called with 10 and 4 as arguments, and the returned value (0) is assigned to $c.
  Finally, the code prints the values of $a < / s t r o n g >, < s t r o n g >$ b, and $c.
Tracing the Output:
$a remains 10 (it is not modified within the function because of pass-by-value).
$b < / s t r o n g > r e main s 4 (t h ec han g e in s i d e t h e f u n c t i o n d oes n^{'} t a f f ec tt h e g l o ba l < s t r o n g >$ b).
$c becomes 0 (the return value of the function).
Therefore, the code will print "1040". Correct Option:
The correct answer is Option A: 1040