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Question
What happens to light passing through even thin clouds of dust?A) The light that passes through them is blue shifted due to the cloud's approach.
B) It dims and reddens the light of all more distant stars.
C) Even a little can completely block all light, such as the Horsehead Nebula.
D) Its motion causes the light of stars beyond to twinkle.
E) Its motion causes all light to be red shifted as it passes through these clouds.
Answer
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