Thanks @DumbHollywoodActor for the very helpful answer. It is hence the order of the quantities of the gases that is the crux of the argument. The gold/silver/bronze medal analogy is great.
> @NathanMMolina said:
> Are there many things more dangerous on this test than a Sufficient Assumption answer choice in a Necessary Assumption question? It's like trying to distinguish a blueberry from something that looks like a blueberry ...
This is one where the negation test comes in handy. Negated, (C) says "The notion of blah blah has **NO** analog in organisms." If it truly has no analog, then how could the analogy stand?