the first thing is to identify the conclusion.
The conclusion of this argument is: a high fee will alleviate the city traffic congestion.
So any option that says that people are willing to pay extra money, will weaken the argument (i.e. weaken the conclusion).
B says that parking cost already makes it costlier for people to use private vehicle than bus.so people are already paying more than bus for using their private vehicle. So a further increase of 5 $ wud not add much to people woes.
Note that considerably more expensive >> 5$.
D: Many does not means majority.
