x+3>1 is the same as x>-2.
b cannot be true, because, for example, -3 is less than -1 and -2, so it’s not greater than -2.
a and d are both true in a general sense because any value greater than -1 is also greater than -2.
However, c is a specific value of x which is greater than -2, and if only one option is to be chosen, I’d go for c:
-1+3=2>1.