This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Muscle, Subject name: Physiology
[{'content': 'A cross-sectional view of a skeletal muscle fiber through the H-zone would show the presence of: \nSelect and explain. \nA. Actin & myosin, B. Titin & myosin, C. Actin & titin, D. Myosin only', 'role': 'user'}, {'content': 'Answer: D \nExplanation: H-zone is at the center of the sarcomere. Cross-sectional view through the H-zone will show only thick filaments, as ends of the thin filaments stop sho of the center of the sarcomere.', 'role': 'assistant'}]