What will be the output of the following C++ code?

#include <stdio.h>
int main()
{
   const int x;
   x = 10;
   printf("%d", x);
   return 0;
}

A. .cpp B. .cc C. .cxx D. .c

A. char B. float C. boolean D. double

A. File output stream B. File input stream C. Standard output stream D. Standard input stream

A. struct B. interface C. class D. object