The following sentence has been split into four segments. Identify the segment that contains a grammatical error.
The company specialises at / designing, crafting and manufacturing / exquisite, high-quality furniture / of exceptional craftsmanship.

Correct option is C

Option (c) contains an error.
Explanation:
· The verb "specialises" is followed by "in" and not "at."
· The correct preposition with "specialise" is "in" when referring to a specific field or activity.
Correct sentence:
"The company specialises in designing, crafting, and manufacturing exquisite, high-quality furniture of exceptional craftsmanship."
Grammatical Rule Used:
· The verb "specialise" is always followed by "in" + [noun/gerund].
· Example: He specialises in digital marketing. (✔ Correct)
· Incorrect: He specialises at digital marketing. (❌ Incorrect)
Thus, option (c) contains the error. ✅