How to declare an integer variable which can except null? a) int? x b) <nullable>int x c) int x IS NULL d) int ISNULL(X)

int? x;

Hi you can declare like that, this is call nullable type of variable int? i = 50; double? d1 =4.4; bool? flag = null; char? letter = 'h'; int?[] arr = new int?[20]; string is not a nullable type

a,b