Diminishing marginal product suggests that:

A: Additioanl units of output become less costly as more output is produced.

B: Marginal cost is upward-sloping.

C: The firm is at full capacity

D: All of the above are correcr

I am not sure how to answer this one?
Would B be the best answer? A,C, and D don't seem to be correct.

I too would go with B

To answer this question, we need to understand the concept of diminishing marginal product. Diminishing marginal product refers to a situation where the additional output produced from each additional unit of input (such as labor or capital) starts to decrease as more of that input is added, while holding other inputs constant.

Let's evaluate each option to determine which one best describes the concept:

A: Additional units of output become less costly as more output is produced.
This option does not accurately describe diminishing marginal product. Diminishing marginal product is about the decreasing effectiveness of adding more input, not the cost of producing additional units.

B: Marginal cost is upward-sloping.
This option also does not accurately describe diminishing marginal product. Marginal cost refers to the additional cost incurred in producing one additional unit of output, which is not directly related to the concept of diminishing marginal product.

C: The firm is at full capacity.
This option does not accurately describe diminishing marginal product either. Diminishing marginal product does not imply that the firm is at full capacity. It simply means that the additional output produced from each additional input diminishes.

D: All of the above are correct.
Since options A, B, and C are not accurate descriptions of diminishing marginal product, option D cannot be correct.

Based on this evaluation, none of the provided options accurately describe the concept of diminishing marginal product. Therefore, it appears that none of the given answers is correct.