PT158 · S3 · Q19 For there to be a thriving population

This answer says: if the water is NOT acidic, conditions are beneficial. Formally: not acidic → beneficial. But the argument needs the reverse: if the water IS acidic, conditions are NOT beneficial (acidic → not beneficial). This answer provides the wrong direction. Knowing that non-acidic water creates beneficial conditions tells us nothing about what acidic water does. The argument already knows Wallakim is acidic; it needs a rule about what acidity means for turtles, not a rule about what non-acidity means. This is a classic Illegal Negation trap — it affirms the consequence of the condition we need rather than the condition itself.

This answer says water acidity is "the most important factor" determining whether a pond has a thriving turtle population. But "most important" does not mean "decisive." Even if acidity is the most important factor, it could still be outweighed by other favorable conditions at Wallakim Pond. The argument needs a guarantee: acidic water makes conditions not beneficial, period. "Most important factor" leaves room for exceptions — a pond could have acidic water but compensate with other favorable conditions. For a Sufficient Assumption question, the answer must make the conclusion follow with certainty. "Most important" introduces ambiguity about whether the conclusion necessarily follows.

This answer compares Sosachi Pond's conditions to Wallakim's — saying Sosachi is more beneficial. But a relative comparison does not establish whether Wallakim's conditions are beneficial or not in absolute terms. Wallakim's conditions could be "less beneficial than Sosachi's" while still being beneficial enough for turtles to thrive. The argument needs to know whether Wallakim's acidic conditions are beneficial to turtles at all, not how they rank against another pond. Additionally, the argument's conclusion is about Wallakim specifically; a relative comparison between two ponds does not seal the deal about either one in absolute terms.

This answer says: Wallakim would have a thriving turtle population if it were not acidic. Formally: not acidic → thriving. But the argument does not conclude what WOULD happen if Wallakim were not acidic — it concludes what IS happening given that it IS acidic. This answer tells us about a hypothetical non-acidic Wallakim, but the argument needs to handle the actual acidic Wallakim. Furthermore, even knowing that removing acidity would allow turtles to thrive does not prove that acidity prevents thriving — it could be that acidity is one obstacle among many, and removing it would remove one obstacle while others remain. The argument needs: acidic → not beneficial → not thriving.