The following ordered pairs (x, y) define the relation q.

q = {(-1, 4), (-2, 3), (4, 4), (2, -2)}

is q a function?

a) no, because there is more than one x value from some y values

b) yes, because there is exactly one y value for every x value

c) yes, because there is exactly one x value for every y value

d) no, because there is more than one y value for every x value