If len is the length of the string and num is the number of > characters printed on the screen > Give the relation between num and len. > > void abc (char *s){ > if(s[0]=='�') > return; > > abc(s+1); > abc(s+1); > printf("%c ", s[0]); > > } > > a) num=2^len > b )num=2^len-1 > c) num=2*len-1 > d) None of the above