JEE Main 2020 Mathematics question

If R = {(x, y) : x, y ∈ Z, } is a relation on the set of integers Z, then the domain of is:

• (A){–2, –1, 1, 2}
• (B){–1, 0, 1}Correct
• (C){–2, –1, 0, 1, 2}
• (D){0, 1}