With a Cubic Production Function of the Form $Q = a K ^ { 3 } L ^ { 3 } + b K ^ { 2 } L ^ { 2 }$

Multiple Choice

With a cubic production function of the form $Q = a K ^ { 3 } L ^ { 3 } + b K ^ { 2 } L ^ { 2 }$ , in order for the average and marginal product functions to have their theoretical properties, it must be the case that

A) a < 0, b > 0
B) a > 0, b < 0
C) a < 0, b < 0
D) a > 0, b > 0