Here's the solution:
Let's first look at the splits available in the answer choices. Clearly, the smaller v/s less v/s lessening is the most important split.
Note that 'commitment' is not something that could be counted or measured tangibly.
So, we cannot use 'smaller' to qualify commitment.
For this reason, we can straight away eliminate options A and C
Now, between less and lessening, the latter indicates something that is ongoing. In GMAT, always prefer the simple tense form. So, we can eliminate option E
Between options B and D
, work and career are two things that are directly compared to parents and grandparents in option B. However, the comparison should be between the work and career of parents and grandparents with the work and career of the young people in US. For this reason, option B is incorrect.Option D
clearly compares the work and careers of the young people in US with that of their parents and grandparents by using the verb 'had'. Hence this is the correct answer choice.
Hope this helps
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