//file1.h#define USD 1

//file2.h#define UKP 1

//file3
#include <stdio.h>
#include <file1.h>           //A
#ifdef USD                   // B#define currency_rate 46     //C#endif//D

#ifdef UKP               // E#define currency_rate 100 //F#endif//G
main()
{        
    int rs;
    rs = 10 * currency_rate;  //H
    printf (“%d\n”, rs);
}