Question

Which relation is a function?
A (4,-1),(5,-1),(2,3),(3,2)
B (3,2),(4,-1),(3,8).(-1,4)
C (-1,4),(-2,5),(-3,6),(-2,7)
D (2,2),(3,3),(2,3),(3,2)

Answer 1

From what I remember, I think something can only be a function if an input has only one output

Answer 2

A (4,-1),(5,-1),(2,3),(3,2)

Answer 3

yep

Answer 4

a function is either a one-to-one relation or many-tp one
B,C and D are all one-to-many