低成分乳形成的原因有（）。
A.撇油
B.加水
C.遗传
D.饲养管理
E.挤乳操作
参考答案：A, B, C, D
Professor White has written some short stories, but he is _____ for his plays.
A．more-known
B．the most- known
C．better- known
D．the best- known
注册安全工程师以个人名义承接业务、收取费用，由执业证颁发机关吊销其执业证，当事人（）年内不得再次申请注册
A.1
B.3
C.5
