GMAT Sentence Correction (SC) | Why painting the face and perfuming the body should have persisted

Hir19 ,

Why.... has been the reason is the correct form.

Whenever phrases are used as a subject, they are always singular, hence take a singular verb.

Let me give you an example:

The reason I didn't attend the party and didn't attend the meeting is that I was sick.

Here the reason for both actions is just the same. Did you
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