A. Recently research
suggest that much of the junk serves to regulate when genes are translated into proteins, and how much protein is thus produced.
Subject-Verb doesn't agree in number. SIngular verb "research" requires plural verb "sugests"
INCORRECTB. Much of the junk
serves to regulate when genes are translated into proteins, and how much protein is thus produced, and is suggested by recent research.
"Much of the junk" is plural and requires plural verb "suggest"
INCORRECTC.
Recently research suggests much of the junk serves to regulate when genes are translated into proteins, and how much protein is thus produced.
Adjective "recent" is correct usage instead of adverb "recently" This also missed "that" after "suggests"
INCORRECTD. Recent research suggests
that much of the junk serves to regulate when genes are translated into proteins, and how much protein is thus produced.
E. Recent research suggests much of the junk serves to regulate when genes are translated into proteins, and how much protein is thus produced.
After "suggests", "that" should be present followed by a clause.
INCORRECTHence option D