Explanation

The sentence tells us that the earliest development of silk production has left "almost no archaeological trace." Because there is a lack of physical evidence, any scholarly attempt to reconstruct its history has been blocked, and no definitive or universally accepted story of its true beginnings exists.

Evaluate Blank (ii) First:

The sentence mentions tracking "true beginnings" and the "earliest development" over time. We are looking for a word that means the path, development, or historical course of silk production.

D. proliferation means rapid increase or spread. While silk did spread, the clue focuses on its reconstruction and beginnings.

E. trajectory means a path, course, or line of development. "Historical trajectory" fits perfectly because scholars are trying to chart the course of how silk production started and evolved.

F. versatility means adaptability or having many uses. This does not fit a historical timeline or reconstruction.

Evaluate Blank (i):

The second clause states that "no ______ account of its true beginnings has ever been established." This parallels the first blank. If no definitive account has been established, it means the reconstruction attempts have not yielded anything certain or undeniable.

A. incontrovertible means indisputable or undeniable. A "no incontrovertible account" matches the idea that the true beginnings haven't been firmly established because of the lack of archaeological traces.

B. cursory means hasty or superficial. This contradicts "scholarly attempt at reconstruction."

C. fortuitous means happening by accident or chance. This is irrelevant to the accuracy or certainty of an account.

Answer: A,E