When signing "She is my mother," she is signed with a closed five handshape facing the person
closed five hand touching the signer's chest
pointed finger on the signer's chest
pointed finger toward area of person

absolute strength refers to the maximum force exerted by a body irrespective of body size. relative strength on the other hand is the force exerted by a body in relation to muscle size or body weight.

so the answer is: c. absolute strength measures strength regardless of your body size, while relative strength measures strength adjusted for your weight.