麻烦各位帮忙解个题，万分感激啊~ total, increase, addition, 不胜感激

Luccifero

Assume that Notasled, a producer of cafeteria trays, operates in a perfectly competitive market. In addition, assume that the market price is $3.25. Notasled will increase production so long as:



A)    marginal revenue is positive.



B)   marginal revenue is greater than $3.25.



C)   marginal cost is less than $3.25.



D)   total revenue is increasing.


正确答案是C，但是D到底错在哪里了？麻烦各位了，不胜感激~

Luccifero

Thanks very much~