The author’s argument rests on the unsubstantiated as assumption that B and D are sufficiently alike in ways that might affect the impact of A. However, they might differ in some aspects. For example, B might lack something. For that matter, perhaps B is… If so, A is not a reasonable solution for the problem.
Example
Finally, the mayor's argument rests on the unsubstantiated assumption that Hopewell and Ocean View are sufficiently alike in ways that might affect the economic impact of a new golf course and hotel. Hopewell might lack the sort of natural environment that would attract more tourists and new businesses to the town--regardless of its new golf course and hotel. For that matter, perhaps Hopewell already contains several resort hotels and golf courses that are not utilized to their capacity. If so, building yet another golf course and hotel might amount to a misallocation of the town's resources--and actually harm the town's overall economy. (AA23)
Even if A is to be attributable to C, it is possible that C is dissimilar to B. For example, in B … while C … If so, then the fact that C would amount to scant evidence at best that A would achieve B.
Example
Even if Schade is to be credited for the band's awards, it is possible that the skills that Schade possesses and which resulted in the band's winning these awards are not the same skills required for the district position. For example, perhaps Schade's music-conducting ability or his ability to motivate individual students was responsible for the band's award winning performances. If so, then the fact that Steel's band won these awards would amount to scant evidence at best that Schade would make an effective administrator for the district. (AA24)
The statistical reliability of the survey’s results is questionable. The number of participants, N, might constitute an insufficiently small sample to draw any reliable conclusions about {the problem}. The larger the overall population of B compared to the sample of N participants, the less reliable the survey’s results. Also, the sample might be unrepresentative of all population of B. For example, perhaps the N participants happened to be those ones who are what. Lacking assurance that the N participants are statistically representative of all population, the author cannot draw any reliable conclusion based on the survey.
Example
Even if the participants' punctual and regular attendance was due to the breakfasts provided to them, the statistical reliability of the trial program's results is questionable. The number of participants, 100, might constitute an insufficiently small sample to draw any reliable conclusions about how district students 5-12 years of age would behave under similar conditions---as a group. The larger this group compared to the sample of 100 participants, the less reliable the study's results. Also, the sample might be unrepresentative of district students as a group. For example, perhaps the 100 participants happened to be children who eat small dinners and are therefore hungry for breakfast. (AA26)
The argument assumes that A and B are mutual exclusive alternatives and there is no room for a middle ground or other choices. However, no evidence is provided to substantiate this assumption. In fact, the author overlooks the possibility that both A and B may happen together, resulting a better solution. Similarly, it is also possible that C would happen. Either case, if true, would serve to undermine the author’s claim that B would happen.
Example
Finally, the argument suffers from "either-or" reasoning. Based on the fact that Monroetown residents are opposed to Brown's proposed tax cut, the author unfairly concludes that they must be in favor of Greene's proposal. However, the author overlooks the possibility that Monroetown residents are not in favor of either proposal.
