Based on what you know of the relationship between the thick and the thin filaments

Assuming that the question has asked about the event that might occur if an individual has a disease in which no tropomyosin is produced in the body.

Actin and myosin filaments play an important role in the muscle contraction. Actin consists of thin filament whereas myosin consists of thick filament. Tropomyosin is present in association with troponin to cause muscle contraction.

If the individual has disease and cannot produce tropomyosin, the muscle tissue of his body will remain in the contract position and not able to relax. The tropomyosin is involved in covering the binding site of myosin with actin. The absence of tropomyosin will open the myosin binding with actin continuously and no relaxation of muscle will occur.    

substitution is the answer in this case

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation: