Question

an interaction between two organisms in which one usually benefits is known as
symbiosis
mutualism
endosymbiosis

Explanation:

1. Analyze each option:

• Symbiosis: A close and long - term interaction between two different biological organisms. It can include relationships where one or both benefit, or one benefits and the other is harmed or unaffected. So this is a general term for interactions between two organisms, which can include cases where one benefits.
• Mutualism: A type of symbiosis where both organisms benefit from the interaction. The question states "one usually benefits", so mutualism is not correct as it requires both to benefit.
• Endosymbiosis: A type of symbiosis where one organism lives inside the cells of another organism. It is a more specific type of symbiosis and not the general term for an interaction where one usually benefits.

1. Conclusion: The term that refers to an interaction between two organisms in which one usually benefits (along with other possible outcomes for the other organism in different symbiotic sub - types) is symbiosis.

Answer:

symbiosis