单选题 We see distant galaxies as they were long ,long ago because

A、 they were closer together then.
B、 the universe has always looked as the same.
C、 their light takes so long to reach us.
D、 they have travelled such a long way.

【正确答案】 C

【答案解析】[解析]由短文第四段中的“Since the very distant galaxies are thousands of millions of light years away，then we are seeing them as they were thousands of millions of years ago．”可知答案为C。故应选C。