Spider Crabs Live on the Ocean Floor in Shallow Areas

question 65

Multiple Choice

Spider crabs live on the ocean floor in shallow areas and greenish-brown algae live on their backs. This provides the algae with a home and the algae's greenish-brown color helps the crab blend in and stay safe from predators. This association can be considered a mutualism because

• A) both partners receive a net benefit.
• B) the association is an altruistic one.
• C) one partner benefits and the other is not harmed.
• D) the crab obtains a greater net benefit than the algae.

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