Kinesiology is the scientific study of body motion. It involves understanding of the mechanics of motion (muscles, nerves, tendons and joints), plus consideration of control of motions by the central nervous system (brain and spinal cord). It also incorporates an understanding of the effect on motion of psychology.
In this latter aspect, the psychology of motion, the term “Kinesics” was coined to encompass the study of “body language” or so called “non-verbal communication” as expressed by facial expressions, gestures and posture.
Thus, the answer to the multiple choices shown in your question is
b. Non-verbal communication
Kinesics makes use of the observation of movement of any body part, or of the body as a whole. Such observation ranges from observance of a subtle facial expression to the posture of the entire body.