单选

Passage Two

A scientist once said: “I have concluded that the earth is being visited by intelligently controlled vehicles from outer space.”
If we take this as a reasonable explanation for UFOs (unidentified flying objects), questions immediately come up. “Why don’t they get in touch with us, then? Why don’t they land right on the White House lawn and declare themselves?” people asked. In repl
Are we being observed by intelligent beings from other civilizations in the universe? Are they watching our progress in space travel? Do we live in a gigantic “zoo” observed by our “keepers”, but having no communication with them? N
A. there are no such things as UFOs
B. UFOs are visitors from solar system
C. there’s no reason for UFOs sooner or later
D. we are bound to see UFOs sooner or later

试题出自试卷《2012年1月全国自主考试综合英语(一)真题及答案》

参考答案