The following sentence has been split into four segments. Identify the segment that contains a grammatical error.
Scientists believe / that many animals have / a unique languages / of their own.

Correct option is C

Option (c) contains an error.
Explanation:
The phrase "a unique languages" is grammatically incorrect because "a" (a singular article) cannot be used before the plural noun "languages."
The correct phrase should be "a unique language" (singular) or "unique languages" (without "a") if plural is intended.
Grammatical Rule Used:
· "A" and "An" are used with singular countable nouns.
· Plural nouns do not take "a" or "an."
Example:
❌ She speaks a foreign languages. (Incorrect)
✅ She speaks a foreign language. (Correct)
Meanings of other options:
· (a) that many animals have – Correct, no grammatical issue.
· (b) Scientists believe – Correct, subject-verb agreement is maintained.
· (d) of their own – Correct, no errors.