Thanks for posting
cck2_waikato!
I can absolutely see how it would be tempting to think
(B) supported the argument here. But let's step back for a moment and think about what it means to support the premises.
Let's say you have the argument:
PREMISE: All boys like sports
CONCLUSION: Therefore, Andy likes sports
The gap in the argument is that we are assuming that Andy is a boy! So, to support the argument, or strengthen it, we might say that Andy IS a boy, or perhaps that it is likely that Andy is a boy.
But what about a statement that a recent study showed that every boy interviewed did, indeed, like sports. Does that support the argument? Well, it doesn't help our big yawning gap. It's boosting up the
premise. But we already know the premise is true! We are required to accept the premise when we evaluate the argument. If we don't accept the premise, then we are essentially trying to evaluate the
truth of the argument, rather than evaluate the logic as the argument moves from accepted-premise to debated-conclusion!
This is the reason that "premise booster" answers are incorrect on assumption and strengthen questions. They don't actually strengthen the argument, because they 'boost' the premise,
which is something that you already know to be true.In this example,
(B) might support the idea that demand for energy is reduced. But since
we already know that to be true, this support doesn't actually support the argument.
So, this part of the answer choice doesn't actually strengthen - like any premise booster, it doesn't do anything at all! But that doesn't mean the answer choice is wholly irrelevant. The first clause of
(B) gives us something more useful: that the tax increase will lead to a cleaner environment. That's a big fat PLUS for the tax increase!
Any plus for the tax increase damages the argument that the tax increase will do more harm than good! So
(B) does weaken the argument once we focus on the first half of the sentence, instead of the second half!
In a
Weaken EXCEPT question you will always have
four weakeners, and
one answer that is either a strengthener or irrelevant. You can rest assured that you will never have two answer choices where one is irrelevant and the other is a strengthener and you have to choose - so if you ever feel that you are faced with that, you need to completely reassess your analysis of the answers!
Does that help clear things up a bit?