Variable Number of Arguments - Programming

Q1:

Point out the error in the following program.
#include<stdio.h>
#include<stdarg.h>

int main()
{
    void display(int num, ...);
    display(4, 12.5, 13.5, 14.5, 44.3);
    return 0;
}
void display(int num, ...)
{
    float c; int j;
    va_list ptr;
    va_start(ptr, num);
    for(j=1; j<=num; j++)
    {
        c = va_arg(ptr, float);
        printf('%f', c);
    }
}

A Error: invalid va_list declaration

B Error: var c data type mismatch

C No error

D No error and Nothing will print

ANS:A - Error: invalid va_list declaration

Use double instead of float in float c;