Q15 - A favored theory to explain the extinction

[WaltGrace1983]

This is the assumption question of the two-part "favored theory" bunch. The question is saying that there are two theories for dinosaur extinctions: the new one and the old one. This question is focusing on the new theory. After giving the new theory, it gives an example pertaining to the new theory by stating that there is a region in India in which volcanic flows are correlated in time with the extinctions (and the asteroid impact...hmmm fishy).

A massive volcano activity that caused the extinctions by putting enough dust into the atmosphere to cool the planet
→
Any asteroid impact was irrelevant

The first thing to notice here is how strong that conclusion is. It is not merely saying that the asteroid impact was not the cause of the extinctions, no no no. It is saying that any asteroid impact was irrelevant. In other words, even if the asteroid impact didn't occur, did occur, or occurred differently, it doesn't matter at all. This is going to be a huge thing to think about when we attack the answer choices. Maybe there is some causal explanation for the volcanic activity. Maybe the asteroid impact triggered a series of events that triggered the volcanic activity.

This is what (A) gets at. It says that there is no causal connection between the volcanic activity and the asteroid impact. Try to negate it and see what happens: "The massive volcanic activity was caused by the impact of an asteroid." If we assume the negation then all of a sudden our conclusion doesn't look so hot anymore. Let's look at the other answer choices.

(B) The extinction doesn't have to be immediate. The volcanic activity could have still caused the extinction by triggering certain events that would eventually wipe out the dinosaurs in a few days, months, etc.

(C) This is very similar to (B). However, we just simply don't care about how long the period of time was that the extinction occurred over. The point is that the extinction did take place and it was caused by the volcanoes.

(D) This might actually hurt the argument. Imagine if only one region was experiencing volcano flows. Could this produce an entire extinction? Probably not.

(E) This is by far the most tempting answer. This was one of those that looks a lot better once you see the right answer but let's pretend that we haven't seen (A) yet. The reason why you can eliminate this is because, even if it were possible to see what came first, what does that prove? So the asteroid came first? So what? Does this help us determine if the asteroid was irrelevant? It may weaken the new theory's argument but we have to remember that we are making the assumption that the asteroid did come first. What if we assumed the opposite way? What if we said that the volcanic activity came first? That probably strengthens the new theory's argument! See, with an answer choice like this, it doesn't really help us with the argument at all and if we have to make further assumptions to make this help the argument then it usually bad news.

In addition, evaluate how specific the answer choice is. We are only talking about the Deccan flows. What if those were not correlated in time with the rest of the volcanic flows?

I'd love some feedback on (E) if anyone has anything more to add!