A Manager in Charge of New Product Development Can Hire

A manager in charge of new product development can hire engineers and market researchers. The annual salary of an engineer is $40,000, while a market researcher receives $20,000. The marginal contributions of engineers and market researchers are:

$\begin{array}{cccc}\text { Engineers }(E) &&\text { Market Researchers }(R) \\&\text { Additional }&&\text { Additional }\\\text { Worker } & \text { NewProducts } & \text { Worker } & \text { NewProducts }\\1^{\text {st }} & 50 & 1^{\text {st }} & 20 \\2^{\text {nd }} & 40 & 2^{\text {nd }} & 15 \\3^{\text {rd }} & 30 & 3^{\text {rd }} & 10 \\4^{\text {th }} & 20 & 4^{\text {th }} & 5 \\5^{\text {th }} & 10 & 5^{\text {th }} & 2\end{array}$
-If the manager currently hires four engineers and one market researcher, what must be true?

A) She is making the correct decision because $M P _ { E } = M P _ { R }$ .
B) More new products would be developed if she hires more engineers and fewer market researchers.
C) More new products would be developed if she hires fewer engineers and more market researchers.
D) She is not making the correct decision because