A duck _____, but a dog barks. [ ]
A. meows
B. quacks
C. squeaks
B
I wondered what difficulty he had _________ the plan?
A．to carry out
B．carrying out
C．carried out
D．with carrying out
根据《刑法》规定，重大劳动安全事故罪的犯罪客体是（）
A.直接负责的主管人员
B.其他直接责任人员
C.公共安全
D.劳动安全
