what are the domain and range of the function {(3, 1), (5, –1), (9, –1), (2, 7), (–4, 1)}?

a. domain: {1, –1, 7}; range: {3, 5, 9, 2, –4}
b. domain: {3, 5, 9, 2 }; range: {1, 7}
c. domain: {1, 7}; range: {3, 5, 9, 2 }
d. domain: {3, 5, 9, 2, –4}; range: {1, –1, 7}