by signing hurt at a specific part of the body what grammatical feature is being used

A. body verb agreement
B. subject body agreement
C. topic comment agreement
D. topic verb agreement

The grammatical feature being used when signing hurt at a specific part of the body is B. subject body agreement. In American Sign Language (ASL), your own body is the subject of the sentence, and the specific body part being referred to acts as the object. Therefore, when signing "hurt" at a specific body part, the sign needs to agree with the subject (your body) and the object (the specific body part) in a grammatical agreement known as subject body agreement.