A relation R is defined form {2, 3, 4, 5} to {3, 6, 7, 10} by x Ry ⟺ x is relatively prime to y. Then, domain of R is (a) {2,3,5} (b) {3,5} (c) {2, 3, 4} (d) {2, 3, 4, 5}