Answer : Option B

Explanation :

The gcvt() function converts a floating-point number to a string. It converts given value to a null-terminated string.

 #include <stdlib.h> #include <stdio.h>  int main(void) {     char str[25];     double num;     int sig = 5; /* significant digits */      /* a regular number */     num = 9.876;     gcvt(num, sig, str);     printf("string = %s\n", str);      /* a negative number */     num = -123.4567;     gcvt(num, sig, str);     printf("string = %s\n", str);      /* scientific notation */     num = 0.678e5;     gcvt(num, sig, str);     printf("string = %s\n", str);      return(0); } 

Output:
string = 9.876
string = -123.46
string = 67800