One item I see that could be construed as an assumption is whether plankton are highly evolved or not. While in real life we know they are not highly evolved, the argument never explicitly states that. This is exactly why I came here! This question did not give me much trouble at first, but reviewi...

That's as much as we're allowed to use for these answer choices. (E) is saying that the last line there shows us that we're definitely using the right medication. How does it show that? There has still been no improvement! I had chosen E for this question, and I see now that it might've been becaus...