The Reluctant Monarch, which Francis Craig wrote as her third in a series of books about the British Monarchy.
To begin, we know that there's a flaw in the sentence structure. The usuage of 'which' leads to a fragment or incomplete sentence and the statement also misses a verb. Hence, we can immediately rule our A and C.
(B) The Reluctant Monarch is the third book written by Francis Craig
( We now have a verb 'is'.So it sorts our primary concern. However, if read the whole statement along with the non-underlined portion, it brings us to question the meaning of the statement. It leaves us questioning who is the 3rd book written by ? 'Francis Craig in a series of books' makes no sense whatsoever.) Out
(D) Francis Craig wrote The Reluctant Monarch, which book is her third ( 'which book is her third' acts like a question rather than a pronoun.) Out
(E) The Reluctant Monarch, written by Francis Craig, is her third (has a verb and makes perfect sense in terms of meaning as well since the modifier 'written by Francis Craig' is immediately after the name of the book he has written. )
OA: E
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