In the table below, fill in the numeric answers in the "Willingness to Pay" (WTP) blanks where indicated. WTPx, WTPy, WTPz represent three different individual's "willingness to pay".

Q	MC	WTPx	WTPy	WTPz	CollectiveWTP
1	28	24	15	17
2	35	16		9	34
3	37		7	6	27
4	39	12	5		21
5	43	11	4	3

What is the optimal quantity of the public good that should be provided?

a) 1

b) 2

c) 3

d) 4

e) 5