PT5.S1.Q3 Plainsville Mayor building highway

So this was a very interesting question. We are asked to identify the necessary assumption in the argument of the citizens group. Citizen group argues that the mayor have more than the town's economic interest in mind. Why? the citizens give the answer that the mayor didn't go with what they think is the BETTER option: building a park. Comparing to the highway, the citizens believe that the park will attract TWICE as much business.

What is the problem here? Well, how do we know that just because the mayor didn't go with what the citizens think as the best option, he's in bed with the highway construction company? There might be other concerns that the mayor considers other than just maxing out the business that plainsville can attract, such as pollution brought by making a business park by cutting down trees, land shortages, etc.. These can definitely make the highway more attractive to the mayor than the business park, leading the mayor to think the best option for the economy is the highway. More importantly, the mayor can just simply be unaware of the idea of the business park. He simply did not consider that option, and when the citizen group roasts him for it, he's like damn you're right let's build a park. The citizen group, therefore, has to assume that the mayor has considered the park, knows about its advantages over the highway, and think it is economically more ideal to build a park than to build a highway to make the conclusion that the mayor is interested in more than pure economic gain for the city.

The necessary assumption therefore should be something like: the mayor recognizes that the park is a better option for the economy and can attract more business. Exactly what answer B catches. The mayor has to accept that the park is economically a superior option to the highway. If he doesn't, he can genuinely think that the highway helps the most, with all other things considered (beyond the scope of this question.)

Let's talk about other answers:
A: This doesn't help. Simply beyond what we need to consider here. The citizen group doesn't have to assume that there is already a highway to argue that the mayor is acting sketchy. I don't even see what this answer choice is trying to do. Saying that the highway is important and we don't have it yet so we need one?

C: We don't need this. The highway not having other benefits does not affect the argument of the citizen group, and the OTHER benefits of the highway is not in the debate between citizens and the mayor. There can well be other benefits from the highway, and the park can still be twice as more beneficial.

D : No idea what tax revenue and approval have to do with the question.

E: I chose this one, thinking hey if the only way to help the economy is to build the park, and the mayor is not building the park, he must have something to hide, right? No. If this question is a strengthening question, this AC could work, but it is not required. The citizens do agree that the highway is bringing SOME economic benefits, implied by the statement that the park can bring twice as much business. Therefore, the citizens don't think that the ONLY way to help with the economy is to build a new park. They don't have to think this to be the case to reach the conclusion that the mayor has other interest in mind. Keep in mind: the citizen's argument is not that the mayor is not helping the economy at all but that he has other interests. This answer choice is too extreme for it to be necessary.