nitish2007
B) When a species is down to just a handful of members, then saving the whole species would entail for caring for each individual as well.
The reason OA is not B is 2 fold:
1. We have to weaken the conclusion which happens to be the last sentence:
Conservation interventions must therefore be guided by scientific evidence and social practicality, rather than emotion. Therefore sort of gives it away and B does not deal with this sentence. 2. Even if we argue about the overall argument, the details are a bit longer. Weakening something entails breaking the argument (strong weaken) or casting doubt (subtle weaken).
In this case, it is telling us that in some case, an edge case, where there are just a few individual left, we would be caring for them but that's a by product of the situation, meaning you will be forced to care for them individually just because there are so few, not because that's the right thing to do but just out of necessity, so the result may be the same but for the wrong reason.
As the result, we did not weaken the argument. The argument still stands and we did not weaken the conclusion either.
P.S. In absence of other weakeners, this could pass up as a subtle weakener, very subtle but not in this case where D is stronger and D actually addresses the conclusion.