A-A+
Why did it take the scientists so long a time
问题详情
Why did it take the scientists so long a time to find the new planets？
A．Because they are much darker than their parent stars.
B．Because there are too many of them.
C．Because there is too much light in the universe.
D．Because they are next to a huge explosion.
参考答案
正确答案：A
解析：当问及为何要这么长时间时，这个天文学家给出的直接回答是：They are a billion times dimmer than their parent stars．dim的意思是“暗淡无光”。
