What is the difference between the following 2 codes?

#include <stdio.h> //Program 2
int main()
{
    int d, a = 1, b = 2;
    d =  a++ +++b;
    printf("%d %d %d", d, a, b);
}

A. No difference as space doesn't make any difference, values of a, b, d are same in both the case

B. Space does make a difference, values of a, b, d are different

C. Program 1 has syntax error, program 2 is not

D. Program 2 has syntax error, program 1 is not

Answer: Option D