Identify the segment in the sentence which contains a grammatical error.
She speaks very highly of both her daughter-in-laws.

Correct option is C

• Error: The term "daughter-in-laws" is incorrect. The correct plural form of "daughter-in-law" is "daughters-in-law."
• Rule Violated: When forming the plural of compound nouns, the plural is generally formed by making the primary noun (in this case, "daughter") plural. The structure here is "daughter-in-law," so the plural form should be "daughters-in-law."

Correction:

• Replace "daughter-in-laws" with "daughters-in-law."