Which of the following can be evidence for the thesis “My boss is not a good boss”?（单选）

A、He is very afraid of taking risks.

B、Our sales was more than one billion dollars before he came, and is only half of that after his arrival.

C、He doesn’t know how to manage a company.

D、None.

正确答案：Our sales was more than one billion dollars before he came, and is only half of that after his arrival.