Ah yes - is vs are. You're right. I think I assumed there'd have to be >1 right answer after reading the options.
It's a remarkably poor question, but option (C) isn't about doubts on the conclusive nature of this specific study, but rather the nature of all studies on all animals. You could credibly argue (and I'd hope a lawyer would!) that no government would base policy on doubting all animal studies and that their position in this case must therefore be due to something about this specific study, e.g. the usage of rats, or the topic of birth defects, or both. So they could argue that (D) is the most logical answer.
Not that it really matters. Pretty clearly the LSAT authors are using the word logical in the street sense of "makes sense" or "sounds plausible" rather than meaning "based on an inference process that's free of fallacies". If DK based their test of competence on questions like this then it doesn't mean much, in my view.
If the validity or significance of the paper depends on whether LSAT questions are fit for DK's purpose, we have entered a much more subjective realm than whether they mishandled the statistical analysis - but as we are there, now, I feel that this particular question is not as bad as it is being portrayed.
Firstly, I think we should put aside the fact that it is labeled as a test of "logical reasoning": it is certainly not a test of formal logical reasoning, and an ambiguous or erroneous label does not necessarily make it a bad question (it is not necessary that it be characterized at all.)
Secondly, we are not logically obliged to accept that it has only one answer among the options presented, though if it has more or less than one while the people who posed it thought it had exactly one, that is a problem (I once was nearly expelled from a class for making this point at greater length than the instructor liked!) On the other hand, the question asks which of the candidate answers is most strongly suggested by the passage, which is not a statement that the others are false.
Here, however, it certainly has no more than one answer among the candidates: there is nothing in the passage that has any bearing on options A, B, D or E
- this is perhaps most obvious in the case of B, but the others are like it. In particular, with respect to D, that specific issue is not raised, and furthermore, if it was the government's opinion now that D was the case to the extent of having a bearing on the decision, there would be no need to explain its position in terms of a potential future determination that the tests are inconclusive.
C, on the other hand, is suggested by the government's explanation: if the tests were conclusive, their future refutation would not be a worry.
As I said, this is not a test of formal logic, where the government's response would not imply the possibility of future refutation. Nevertheless, to explain something on the basis of a premise that is only formally possible would be almost as much an informal fallacy as begging the question, IMHO, and one might suspect it is being offered deceitfully (a concept that has no place at all in logic.)
The sort of analysis of natural language called for here (to see what are and are not the issues being considered) is useful and important, for lawyers and the rest of us, and it is, as I have set out above, more objective than "makes sense" or "sounds plausible." If people were more practiced in analytical reading, then corporations, governments and other organizations would less easily get away with blatant non-sequiturs in their explanations of their positions and actions ("there is no evidence the attackers took any personal or confidential information"...)
It's a remarkably poor question, but option (C) isn't about doubts on the conclusive nature of this specific study, but rather the nature of all studies on all animals. You could credibly argue (and I'd hope a lawyer would!) that no government would base policy on doubting all animal studies and that their position in this case must therefore be due to something about this specific study, e.g. the usage of rats, or the topic of birth defects, or both. So they could argue that (D) is the most logical answer.
Not that it really matters. Pretty clearly the LSAT authors are using the word logical in the street sense of "makes sense" or "sounds plausible" rather than meaning "based on an inference process that's free of fallacies". If DK based their test of competence on questions like this then it doesn't mean much, in my view.