Answer:
Butanoic acid.
Step-by-step explanation:
Muscles can be categorized inside the group of proteins. So, muscles, proteins, cell membranes, and carbohydrates contain essentially elements of carbon, hydrogen, oxygen, and sometimes nitrogen. The structures of these macromolecules or biological molecules are mainly polar.
In the case of butanoic acid, this compound is categorized as nonpolar because commonly, organic simply molecules are nonpolar because of their intermolecular forces and electronegativity differences. The nonpolar molecule would be butanoic acid.