Sentence Correction (SC) | Twenty-two feet long and 10 feet in diameter, the AM-1 is one of the

A) ……the AM1 is one of many new satellites that is a PART OF 15 YEARS effort of subjecting the interactions to scrutiny.

(1st) the use of the singular verb (“is”) in the relative “that” clause doesn’t agree with the logical referent noun: ‘satellites’

It is the ‘satellites’ (plural) that ARE part of the effort.

(2nd) the construction in caps is imprecise and it’s not quite clear what meaning is intended.

Since “15 years” is not written to be a noun-adjective
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