go with C.

d/e - strengthen the argm.

a/b - not relevant to the question at hand

I vote A: residents are only supporting the measure because they expect EVERYONE ELSE BUT THEMSELVES to migrate from driving to rail while they maintain no intention of doing so too. thus a possible outcome may be that only a marginal amount of people use the new system while everyone else continues to grapple with bad traffic.

OA?

I think A.

OA?

I agree with (A) for this same reason

Hi,

Let's first understand the passage:

80% residents favored massive expansion of rail system and were willing to pay through increased taxes.

Now, we need to think: why would this massive expansion not achieve its goal of easing congestion?

Before moving onto the option statements, let's try to prethink:
1. Because the number of new people who would start using highways would be greater than the number of people who would shift from highways to rail system
2. There are some disadvantages associated with rail travel, e.g. stations are not located conveniently, which would make people continue to use highways only

Or anything which suggests that the traffic on the highway is not going to decrease

Now, let's go through the options:

A. most people in favor of expanding the rail system reported less congestion during their highway commute as the primary benefit they would experience - These people are concerned about less congestion on highways. Thus, these people (which form majority) intend to continue to use highways. Thus, this option suggests that the congestion might not decrease much. Let's keep this option aside. It could be the answer.
B. of the less than 20 percent of residents not counted as favoring the expansion, about half claimed to have no opinion one way or the other - This option is talking only about 10% of the people and that too about their opinion on expansion, not whether they will continue to use highways or not. Thus, this option can be eliminated.
C. the twice-daily periods of peak congestion caused by people commuting in cars have grown from about an hour each to almost two and a half hours each in the past 20 years - So, basically this says that the traffic has increased in the last 20 years. But if people start using rail network after its massive expansion, the traffic is epected to come down and congestion should ease. Thus, given option doesn't provide a reason for congestion to continue in the face of rail expansion.
D. expanding the commuter rail system will require the construction of dozens of miles of new railbed - so, this is part of expansion. Since this is part of expansion, funds should be available for this also. How does this affect congestion on highways? It tries to suggest that expansion may not actually take place because it would require construction of miles of roadbed. But the question stem specifically states that "rail expansion, if successfully completed,...". SO, this option statement is not valid and does not provide a reason for continued congestion.
E. the proposed expansion to the commuter rail system will make it possible for some people who both live and work at suburban locations to commute by rail - This should ease congestion. Just the opposite of what we are looking for.

So, after going through the options, we see that only option A is the choice which provides a reason for continued congestion and thus, this is the correct answer.

Hope this helps

Feel free to ask if any clarification is required.

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Regards,
Chiranjeev
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