Explanation

The clue to the last blank is next month, so the missing word must mean coming or about to happen.

Impending is the best match, and neither of the two other choices is supported. For the first blank, the clue is that the memoir allows distinguished figures to tell us about experiences and wisdom learned, so the missing word must mean write about.

Extemporize means to improvise, which is incorrect because Grant wrote an actual account, and exagitate is incorrect because there is no suggestion of his stirring up or censuring.

Expatiate, which means to write about in detail, is the best fit.

For the second blank, note the contrast between the significant works of distinguished figures and the experience of a fly-by-night internet celebrity. The missing word will mean insignificant. Apocryphal is incorrect because the writings are not necessarily fictional, and eccentric is incorrect because there’s no context to support the experiences being unusual.

That leaves petty, which fits the context of the sentence.

Hence options A, E and I are correct!
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isn’t B the solution for the blank (i)?

Why do you think it is B?
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Expatiate means to write about so it’s the appropriate one for Blank (I).

Yes totally. I agree. reading carefully answer choice B is the right one for the first blank.

Fixed.
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They're responding to the fact that though you say B is the correct response for the first blank, A is the response the key gives. Have a look see.

B,E, I

what does exagitate mean?

To agitate. Not quite or nervous, actually.

Regards
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