环境致癌因素包括（）。
A.生物致癌因素
B.物理致癌因素
C.化学致癌因素
D.以上均是
E.以上均不是
参考答案：D
The employers often give the job to ________they believe have work experience with strong sense of duty.
A．whichever
B．those who
C．who
D．whomever
