Identify the segment of the sentence that contains a grammatical error.

A. The article B. that you shared C. was both insightful D. and inform.

The correct answer is and inform.

Explanation:

The sentence is: "The article that you shared was both insightful and inform."

In English grammar, the correlative conjunction pair "both ... and ..." requires parallel structure. This means the words or phrases connected by "both" and "and" must belong to the same part of speech.

In the given sentence, the word "insightful" following "both" is an adjective. Therefore, the word following "and" must also be an adjective rather than a verb like "inform".

To correct the grammatical error, "inform" should be replaced with the adjective form, "informative".

Corrected Sentence: "The article that you shared was both insightful and informative."

Thus, the segment containing the grammatical error is and inform.