Which of the following is the correct output for the program

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Which of the following is the correct output for the program given below?

#include<studio.h>
int main()
{
   union a
   { 
        short int i;
        char ch[1];
   };
   union a u;
   u.ch[0] = 10;
   u.ch[1] = 20;
   printf("%d %d %d\n", u.ch[0], u.ch[1], u.i);
   return 0;
}

1. 10 20 5130
2. 5130 10 20
3. 10 20 50
4. None of the above

Correct Option: A

The system will allocate 2 bytes for the union.
First byte for ch[0] i.e. for 10 = 00001010
Second byte for ch[1] i.e. for 20 = 000010100

Combining these 2 we get 00001010 000010100 which is equivalent to 5130 in decimal.

So answer will be 10 20 5130