What is a muscular force?
A. Force due to gravity
B. Force due to charges
C. Force resulting due to action of muscles
D. Force resulting due to rubbing

Hint: As the name suggests, muscular forces are caused by the tension and elongation of different muscles in a body. Muscles usually have a pulling or pushing motion. Muscles in a body attach to the bones of the body. When the muscles contract or elongate, they push or pull on the bones and help in the movement of the body.

Complete step by step answer:
A muscular force, as suggested by the name, is caused by the muscles in a body. The muscles in a body can contract and elongate and thus exhibit a pulling or pushing motion. The main movement caused in a body is brought about by the skeletal muscles. Skeletal muscles attach to the bones of the body and thus, when they contract or elongate, they push or pull on the bones of the body and thereby, bring about movement.
Therefore, everyday activities like running, walking, lifting a box, etc. are the result of the action of muscular forces.
Therefore, the correct option is C) force resulting due to the action of muscles.

Additional information:
Usually, in a specific part of the body, a group of muscles act together to bring about movement. In this group each muscle either affects a pull or push movement. For example, in the arm, the biceps are pulling muscles, while the triceps are pushing muscles.

Note: This problem could have even been solved by applying common logic and by elimination of options. The force due to gravity is the gravitational force while the force due to charges is the Coulomb force. Forces resulting due to rubbing cannot be classified specifically as muscular forces because they rubbing can be brought about by machines also.
Hence, the only option that remains, that is, C) must be the correct answer.