What will be the output of the following C code (after linking to source file having definition of ary1)?

#include <stdio.h>
int main()
{
    extern ary1[];
    printf("%d\n", ary1[0]);
}

A. Value of ary1[0];

B. Compile time error due to multiple definition

C. Compile time error because size of array is not provided

D. Compile time error because datatype of array is not provided

Answer: Option D