Which one of the following, if true, would most strengthen the conclusions of Molina and Rowland concerning the long-...

Rozanna on December 16, 2020

Sorry I meant why is the answer not C?

shunhe on December 18, 2020

Hi @Rozanna,

Thanks for the question! We’re asked here for something that would most strengthen M&R’s argument about the long-term effects of CFCs in the stratosphere. Step one: figuring out what this argument is. Take a look at the third paragraph. There, we’re told that long-term effects would be depleting the ozone layer, even if CFCs stopped going into the atmosphere. So we want something that would help support this idea.

Now let’s take a look at (A), which tells us that an ozone hole over Antarctica kept growing, even though CFC emissions stopped. Well, that’s pretty direct evidence of what M&R were arguing, and so is a good strengthener. Definitely hold on to it, and it ends up being the best of all the answer choices, so it’s the correct answer.

Now let’s take a look at (C), which says that ozone reacts more violently with chlorine than with many other chemicals. OK, but so what? “Many” other could be 3 or 4 others, and “more” could be a fraction more. That doesn’t strengthen nearly as much as (A) does, and so (A) is correct.

Hope this helps! Feel free to ask any other questions that you might have.