(One of the major drawback of cleanliness drives is) less action and more talks.

Options

A. One of the major drawbacks of cleanliness drives is
B. One of the major drawbacks of cleanliness drives are
C. One of the major weakpoint of cleanliness drives is
D. No Improvement

Answer

A

Explanation

One of is followed by a Plural Noun/Pronoun but a Singular Verb.
Hence, One of the major drawbacks (Plural) of cleanliness drives is (Singular) is the right usage.