During execution of a project which is performed for a customer on a T & M (time and material)contract base, a new project manager is taking over the assignment. He discovers that two members assigned to the project have charged time without performing any work for the project customer. Upon further investigation, he determines that this occurred because there have been no other project assignments open for these employees. The customer is unaware of these facts. Which of the following should he do

A) Try to find some productive work for these staff members in the project and leave them on the team.
B) The best thing is to do nothing. The customer will not realize the problem anyway.
C) Try to find a responsible person for the over-assignment who can be made accountable.
D) Take the two people off the team immediately and arrange for the refund of the excess charges to the customer.

一次数学考试共有20道题，规定：答对一题得2分，答错一题扣1分，未答的题不计分。考试结束后，小明共得23分，他想知道自己做错了几道题，但只记得未答的题的数目是个偶数。请你帮助小明计算一下，他答错了多少道题( )

A．3

B．4

C．5

D．6