The correct answer is: E. No error
The sentence is grammatically correct. The word “efficiently” is an adverb that modifies the verb “administered.” The sentence means that the speaker believes that cleanliness in the city is one proof that the civic administration is efficient.
The other options are incorrect because they contain grammatical errors. Option A is incorrect because the word “that” is not necessary after the phrase “I personally feel.” Option B is incorrect because the word “cleanliness” should be followed by a noun, such as “of the city.” Option C is incorrect because the word “is” is not necessary after the word “proof.” Option D is incorrect because the word “efficiently” is an adverb that modifies the verb “administered,” but the verb is not present in the sentence.