Answer:
B. (-2,4), (0,3), (1,6), (-1,2)
Step-by-step explanation:
The list of first numbers for a <em>function</em> is a list of <em>unique</em> numbers.
A: 1 is repeated
B: the 4 pairs have 4 different first numbers: {-2, -1, 0, 1}
C: 1 and 2 are repeated
D: 1 is repeated