This is a weaken question. The argument makes a rather odd claim. Much of the passage concerns the benefits of municipal bonds, including a suggesting that Northopolis issue such a bond. Then the conclusion is that the city will pay for new school buildings with tax revenues. Money from bond issues is not the same thing, so it's unclear what one has to do with the other. To weaken the argument, that distinction--the assumption that issuing a bond will somehow increase tax revenues--must be made clear. Consider each choice:

(A) This is irrelevant, as it doesn't address either the bond issue or the effect of "reluctance" on tax revenues.
(B) This is correct. It relates the existence of the proposed bond issue to tax revenues, which would decrease as a result of the bond issue.
(C) This is irrelevant, as it doesn't address tax revenues.
(D) Again, this choice is irrelevant; the cost of the buildings is not what the conclusion of the argument is about.
(E) This is outside of the scope. If anything, it weakens the argument by suggesting that the bond issue will not have a direct impact on local finances.