Multiple Choice
The object shown in the figure below is a ________ and the dark circles, or "lanes," are mostly likely due to ________. 
A) protoplanetary disk; planets in the process of formation
B) galaxy; star formation
C) protoplanetary disk; infalling gas
D) a single forming planet; moon formation
E) galaxy; infalling gas
Correct Answer:
Verified
Correct Answer:
Verified
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