动物在怀孕期间一般不发情,其主要原因是血液中含有高浓度的()(P152页第34行)
A、卵泡刺激素
B、黄体生成素
C、雌激素
D、孕酮
E、松弛素
参考答案:D
____ the numbers in employment, the hotel industry was the second largest industry in this country last year.
A.In spite of
B.In case of
C.In terms of
D.In praise of
测定酒精度时,必须在25℃的环境下。()