<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:An investigator is developing a drug for muscle spasms. The drug inactivates muscular contraction by blocking the site where calcium ions bind to the myocyte actin filament. Which of the following is the most likely site of action of this drug?? A: Myosin-binding site, B: Myosin head, C: Ryanodine receptor, D: Acetylcholine receptor, E: Troponin C,  <response>: This is a question about the mechanism of muscle contraction and how drugs can inhibit it. The key information in the question stem is that the drug blocks the site where calcium ions bind to actin filaments in muscle cells. During muscle contraction, calcium ions bind to troponin C on the actin filaments, causing a conformational change that allows myosin binding and contraction. Therefore, a drug that blocks calcium binding to actin would inhibit contraction.Of the choices given, troponin C is a regulatory protein on actin that binds calcium ions. This is the most likely target for a drug trying to block calcium binding and muscle contraction. The other choices do not directly interact with calcium or actin.E: Troponin C 