Cut through the crap. In a flaw question, identify what the flaw is precisely and it's easy to spot the answer. It's not like you need to diagram the question and then find the answer that most closely reflects the diagram; the argument in the correct answer might be structured differently (conclusion in a different spot, say) so this approach might confuse things.
A quick diagram might be useful insofar as it helps identify the flaw. In this case the argument goes:
Psych requires the application of stats in order to interpret data. One cannot do this without training in statistics. Therefore, the more training one has, the better they will be at research in psych.
The flaw is that the second premise of the argument states that training in stats is necessary
for experimental psychology, while the conclusion attempts to draw from this that training in stats is sufficient
for making someone better at research in psychology by saying the more training one has, the better they will be. We don't know this from the premises. All we know is that one cannot be good without the training, not that the training guarantees they will be better. So we need to find an answer that makes the same mistake - confusing a necessary condition with a sufficient one.
You don't have to look far.
A) People need the love and support of others. Without it, they are unhappy. Therefore, in most instances, the more love and support a person receives, the happier they will be.
Here, love is put forth as a necessary condition for being happy by the premises of the argument. But, again, the conclusion draws from that premise that love is sufficient to make people happier, just like the first argument did.
Generally, when I find an answer that looks like a very strong contender like this one, I go through the remaining answer choices pretty quickly. As in, I'm ready to toss them out pretty fast if they don't work. If I read a question and my reaction is
after reading it and I already have a very strong contender, I throw it out and move on.
Choices b and c are actually both pretty reasonable sounding arguments after an initial reading, and since I have a strong contender already, I toss them out. D makes an argument that might confuse people once they've made it this far if they're still looking for an answer. It puts forward a necessary condition in one of its premises just like the stimulus did. But it doesn't make the same error of confusing it for a sufficient condition like the stimulus did. Throw it out. With E, the premise puts forward a sufficient condition - an understanding of chemistry will allow one to understand most diseases. It then draws an inference from the sufficient condition that might be unwarranted, but, regardless, there is no point getting bogged down thinking over whether or not this is a good argument or not. Simply by referring to a sufficient condition and drawing an inference from it, rather than doing so from a necessary condition, it's wrong.