The mapping shows a relationship between input and output values.
A mapping diagram shows a relation, using arrows, between input and output for the following ordered pairs: (negative 5, 0), (2, negative 3), (negative 1, negative 3), (4, negative 2), (4, 2), (6, negative 1).
Which ordered pair could be removed to make this relation a function?
a. (–5, 0)
b. (–1, –3)
c. (4, –2)
d. (6, –1)