Here's the soluton:
A quick look at the underlined part will tell you that it should qualify 'lower-end insurance plans' that just precedes the underlined clause. Now, let's take a look at the given options.
Options A and B both begin with 'imposing' suggesting that likelihood of non-union members to be enrolled in lower-end insurance plans is a continuing/continous action. However, here, the 'likelihood' suggests tha the action is something that is desired i.e. it should be in the future tense. Hence, we can straight away rule out these options as incorrect as they have a tense mismatch.
Options C, D and E all begin with 'that'. Hence we need to check the rest of the clause to determine the correct answer choice. As the clause qualifies 'lower-end insurance plans', the various elements in the underlined clause should be parallel and in sync with this.
Let's look at the three elements in the clause -
- impose stricter limits
- require doctors to see more patients
- spend less time with each other
From these elements, it's clear that the 'lower-end insurance plans' can 'impose stricter limits' and 'require doctors to see more patients'. However 'lower-end insurance plans' cannot 'spend less time with each other'. Clearly, 'spending less time with each other' qualifies the doctor and patients. Using the gerund (ing form) of the verb 'spend' will make this refer to doctor and patients correctly.
Hence option D is the correct option which has the first two parts (impose stricter limits and require doctors to see more patients) parallel and the third part qualifying 'doctors' and 'patients' correctly.
Hope this helps!
Cheers.
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