Question

Which set represents a function?

Answer 1

A

Explanation:

A function is in one to one correspondence, that is for any value in the input there is only one unique value in the output

set A satisfies this and is therefore a function.

set B has (2, 1) and (2,4) ← not a function

set C has (3, 4) and (3, 5) and (4, 2), (4, 5) ← not a function

set D has (5, 2) and (5, 3) and (4, 2), (4, 5) ← not a function