If Rice Can Be Produced Using Water and Seed According

Multiple Choice

If rice can be produced using water and seed according to Q = WS,where water,W,costs $3 and seed,S,costs $3,what is the cost-minimizing combination of water and seed capable of producing 144 units of rice?

A) W = 64, S = 0.
B) W = 0, S = 64.
C) W = 1, S = 64.
D) W = 8, S = 8.
E) W = 12, S = 12.