Variable Number of Arguments - Programming

Q1:

Point out the error if any in the following program (Turbo C).
#include<stdio.h>
#include<stdarg.h>
void display(int num, ...);

int main()
{
    display(4, 'A', 'a', 'b', 'c');
    return 0;
}
void display(int num, ...)
{
    char c; int j;
    va_list ptr;
    va_start(ptr, num);
    for(j=1; j<=num; j++)
    {
        c = va_arg(ptr, char);
        printf('%c', c);
    }
}

A Error: unknown variable ptr

B Error: Lvalue required for parameter

C No error and print A a b c

D No error and print 4 A a b c

ANS:A - Error: unknown variable ptr

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