_____, he talks a lot about his favorite singers after class.

A. Quiet a student as he may be  

B. Quiet student as he may be

C. Be a quiet student as he may        

D. Quiet as he may be a student

伪造涂改原始记录或电报：伪造指根本没有进行观测或没有自动观测记录，凭空捏造记录或电报，涂改是指为掩盖错情而将观测记录、电报涂改了，指使记录失真。每发生一次算（）错情.