考博考试

【单选题】Cosmic rays of various kinds come through the air from outer space, but enormous quantities of radiation from the sun are ______ off.
A．avoided
B．excluded
C．screened
D．separated
网考网参考答案：C
网考网解析：
screen off隔开。句意：宇宙中的各种光线从外层空间通过大气层传来，但是太阳的大量辐射能被大气层隔开。A. avoid避免；B．exclude排除；D．separate使隔开，其后不跟off。 查看试题解析出处>>