Yogi eats a sizable quantity of pie by the slice, and generally pays $6 per slice at the vending cart outside his office. When a new vendor on the block begins offering (the same quality) pie at $5 per slice
a. Yogi will continue buying from the old vendor
b. Yogi will buy from the new vendor
c. Yogi will negotiate with both vendors
d. Yogi will stop buying pie