Which of the Following Is Always Wrong, Regardless of What

Multiple Choice

Which of the following is always wrong, regardless of what other information may be given to you?

A) Hiring a worker when her marginal physical product is decreasing.
B) Hiring a worker when her marginal physical product is positive.
C) Hiring a worker when her marginal physical product is increasing.
D) Hiring a worker when her marginal physical product is negative.
E) Hiring a worker when her MRP > W.