Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: If an air mass forms over an ocean it is called a maritime air mass.

Answer: If an air mass forms over an ocean it is called what type of air mass?

Question: The bird ancestor that lived in trees developed wings, which is commonly associated with birds.

Answer: The bird ancestor that lived in trees developed what feature commonly associated with birds?

Question: Strong gravitational fields are capable of altering the rate of time passing.

Answer:
What is capable of altering the rate of time passing?