Question

In commensalism, two organisms have:

• A. Benefit to both
• B. Harm to both
• C. Benefit to one and harm to the other
• D. Benefit to one and neither harm nor benefit to the other

Hint:

Remember: In commensalism, one wins, the other doesn’t lose — it's a neutral relationship for one and beneficial for the other.

Answer 1

The Correct Option is D

Commensalism is a type of symbiotic relationship between two organisms in which one organism benefits while the other is neither helped nor harmed. It differs from mutualism, where both organisms benefit, and parasitism, where one benefits at the expense of the other.
A classic example of commensalism is barnacles growing on whales. The barnacles benefit by gaining mobility and access to nutrient-rich waters as the whale swims, while the whale remains unaffected.
In summary:

• (A) Describes mutualism — incorrect.
• (B) Describes competition — incorrect.
• (C) Describes parasitism — incorrect.
• (D) Describes commensalism — correct.