Consider the following C program:#include <stdio.h> void fX(); int main(){ fX(); return 0; } void fX(){ char a; if((a=getchar()) != ' ') fX(); if(a != ' ') putchar(a); }Assume that the input to the program from the command line is 1234 followed by a newline character. Which one of the following statements is CORRECT?

Let's trace the recursive execution of the function fX() with input `"1234 "`:

1. First Call (fX()):

   • a reads '1'. Since `'1' != '

', it makes a recursive call to fX()`.

2. Second Call (fX()):

   • a reads '2'. Since `'2' != '

', it makes a recursive call to fX()`.

3. Third Call (fX()):

   • a reads '3'. Since `'3' != '

', it makes a recursive call to fX()`.

4. Fourth Call (fX()):

   • a reads '4'. Since `'4' != '

', it makes a recursive call to fX()`.

5. Fifth Call (fX()):

   • a reads `'

'. The condition (a = getchar()) != ''` evaluates to false, so no further recursive call is made.- The next condition `if (a != '')` is also false, so nothing is printed and this call returns to the fourth call.

6. Unwinding the Stack:

   • In the fourth call, a = '4'. putchar('4') prints 4.

   • In the third call, a = '3'. putchar('3') prints 3.

   • In the second call, a = '2'. putchar('2') prints 2.

   • In the first call, a = '1'. putchar('1') prints 1.

After unwinding the recursion, control returns to main(), which returns 0 and terminates.

Thus, the printed output is 4321, making (C) the correct option.