Which of the following statements are true regarding functions?

A. The horizontal line test may be used to determine whether a function is one-to-one.
B. The vertical line test may be used to determine whether a relation is a function.
C. A function is a relation in which multiple values of the input variable are paired with at least one of the output variable.
D. A sequence is a function whose domain is the set of rational numbers.

Question

Which of the following statements are true regarding functions?

 		A.	The horizontal line test may be used to determine whether a function is one-to-one.
 		B.	The vertical line test may be used to determine whether a relation is a function.
 		C.	A function is a relation in which multiple values of the input variable are paired with at least one of the output variable.
 		D.	A sequence is a function whose domain is the set of rational numbers.

anonymous · Answer

I think A and B are right D is wrong, and I am not sure about C