请问张慧雯老师，此题定位thus那句之后，就把C直接排了。可以请老师解释一下这句内逻辑关系，和C选项的对应吗? 谢谢！

请问张慧雯老师，此题定位thus那句之后，就把C直接排了。可以请老师解释一下这句内逻辑关系，和C选项的对应吗? 谢谢！

RC 听了录音 还是不懂

The passage suggests that methiocarb and metaldehyde would be more effective as slug poisons if it were true that they Most farmers attempting to control slugs and snails turn to baited slug poison, or molluscicide, which usually consists of a bran pellet containing either methiocarb or metaldehyde. Both chemicals are neurotoxins that disrupt that part of the brain charged with making the mouth move in a coordinated fashion--the "central pattern generator"--as the slug feeds. Thus, both neurotoxins, while somewhat effective, interfere with the slugs' feeding behavior and limit their ingestion of the poison, increasing the probability that some will stop feeding before receiving a lethal dose. Moreover, slugs are not the only consumers of these poisons: methiocarb may be toxic to a variety of species, including varieties of worms, carabid beetles, and fish. Researchers are experimenting with an alternative compound based on aluminum, which may solve these problems, but this may well have a limited future as we learn more about the hazards of aluminum in the environment. For example, some researchers suggest that acid rain kills trees by mobilizing aluminum in the soil, while others have noted that the human disease Alzheimer's is more prevalent in areas where levels of aluminum in the soil are high. With farmers losing as much as 20 percent of their crops to slugs and snails even after treatment with currently available molluscicides, there is considerable incentive for researchers to come up with better and environmentally safer solutions. (A) disrupt the slug's digestive processes rather than its reproductive functions (B) reduce the slug's ability to taste food (C) begin to affect the feeding behavior of a slug only after it has ingested a lethal dose (D) reach the central pattern generator more quickly (E) accumulate only in the central pattern generator rather than throughout the brain Ans:(C) 38为什么选C不选A呢？ 原文 Thus, both neurotoxins, while somewhat effective, interfere with the slugs' feeding behavior and limit their ingestion of the poison, increasing the probability that some will stop feeding before receiving a lethal dose. 说的是在接受lethal dose之前有一系列的影响呀~C说的是在接受Lethal dose 之后才有影响