Explanation consistent with observations

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Question 1

On a sheltered beach, biologists noticed that small shore crabs occupied empty snail shells near the high-tide line. During 12 morning surveys, recently occupied shells were common beside patches of damp seaweed but rare on equally sandy areas without seaweed. Laboratory trials showed that empty shells placed under damp seaweed stayed cooler and lost moisture more slowly than shells left exposed. The crabs did not eat the seaweed, and both areas contained similar numbers of empty shells before each survey. The observations do not establish which environmental feature the crabs detect. They do, however, suggest that if midday heat becomes more intense, shell sites that retain cool, moist conditions may become increasingly valuable to the crabs.

Which hypothesis is most consistent with all the observations in the text?

AThe crabs favor shells beneath damp seaweed because that cover makes the shells warmer while slowing their moisture loss. BThe crabs favor shells beneath damp seaweed because that cover cools the shells but causes them to lose moisture faster. CThe crabs favor seaweed patches because those patches contain more empty shells before each survey. DThe crabs favor shells beneath damp seaweed because that cover helps the shells remain cool and moist.

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