Answer: [D]: " commensalism " .
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Step-by-step explanation:
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Note: The answer choices listed are examples of "symbiotic relationships" between 2 (two) different species; and these terms are using in biology—more specifically—within the sub-specialty field—ecology.
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In the example provided:
We are given two species: 1) barnacles; and 2) whales;
in which the barnacles benefit ; and the whales aren't affected at all.
So one species (the barnacles) benefit; and the other species is "neither helped nor harmed". In other words: "(+, 0)" —in which "+" represents one species benefiting; and the "0" meaning "neutral"—the other organism/species is neither helped nor harmed.
Let's review the answer choices:
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Choice [A]: "predation" . In this type of symbiotic relationship—also, known as "predator-prey relationship"—one species [the predator] benefits (+), while the other species [the prey] is harmed [wounded or killed and eaten.].
(−) . In other words: "(+, −)" —in which "+" represents one species benefiting; and the "− " meaning "negative"—the other organism/species is harmed.
The example given in the question is NOT: "(+, −)" ; so we can Rule out choice: [A].
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Choice [B]: "parasitism" . Like "Choice {A]" above, this is a: "(+, −)" symbiotic relationship. The parasite is benefited (+) by living on and obtaining nutrients from the host organism, and as such, the host is being harmed by the parasite (−) . Since this is a "(+, −)" relationship, we can rule out Choice: [B].
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Choice [C]: "mutualism" . This is a "(+, +)" symbiotic relationship, in which two organisms/species interact together in a way in which "Species A" benefits from "Species B" ; while "Species B" benefits from "Species A".
This is a "(+, +)" relationship; so we can rule out "Choice: [C]."
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This leaves us with the correct answer: Choice [D]: " commensalism ";
→ the term that describes a "(+, 0)" symbiotic relationship ;
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Note: There is another type of symbiotic relationship known as "amensalism" ; which is a: "(0, − )" relationship.
Note: There are "science terms" (in the disciplines of biology and ecology.).
In non-science related terms, what we colloquially refer to as "symbiosis"—or a "symbiotic relationship"—is actual somewhat like "mutualism" in ecology [see 'Choice: C' above.].
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Hope this is helpful to you!
Best wishes to you with your academic pursuits!
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