ExplanationThe time trigger only later tells you that the earlier feudal system differed from the fullydeveloped version that came later, so the word for the blank needs to mean not fully developed. Both byzantine and labyrinthine are nearly the opposite of what you’re looking for, so eliminate choices (B) and (D). Neither refractory, which means stubborn, nor perfidious, which means disloyal, is supported by the sentence, so eliminate choices (A) and (F).
Both nascent and inchoate can mean not fully formed, so choices (C) and (E) give you appropriate, equivalent sentences.
Hence options C and E are correct!
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