Mathematics

Problem

Which of the following statements best defines a function from a set

A

to a set

B

? a) Every element of

B

is paired with at most one element of

A

. b) No two distinct elements of

A

are paired with the same element of

B

. c) Every element of

A

is paired with exactly one element of

B

. d) Every element of

A

is paired with at least one element of

B

(possibly more than one).