尖锐湿疣的平均潜伏期为()
A．1个月
B．2个月
C．3个月
D．4个月
参考答案：C
胚胎发育过程中，黄斑中心凹出现于()
A．胚胎5个月
B．胚胎6个月
C．胚胎7个月
D．胚胎8个月
E．胚胎9个月
Mr. Yang's daughter is pretty good _____ drawing pictures and won many prizes.[ ]
A. with
B. for
C. in
D. at
