//file1.h#define USD 1

//file2.h#define UKP 1

//file3
#include <stdio.h>
#include <file1.h>               //A#if (defined (USD))                   // B #define currency_rate 46
#elif (defined (UKP))
     #define currency_rate 100          //C#else
     # define currency_rate 1        //D#endif                        

 main()
{        
    int rs;
    rs = 10 * currency_rate;          //H
    printf (“%d\n”, rs);
}