Which of the function definitions for a function isletter will correctly determine whether a character is an alphabetic letter and returns 1 for true and 0 for false? 1. int isletter(char ch) { if((ch >= a && ch <= z)||(ch >= A && ch <= Z)) return 1; else return 0; } 2. int isletter(char ch) { if((ch >= a || ch <= z)&&(ch >= A || ch <= Z)) return 1; else return 0; }