It is considered to be the placing of similar objects into similar groups. In science, it usually is a part of taxonomy, and taxonomy is science of naming living things by putting them into categories. I hope I helped!
C. They produce ATP
The energy required for various chemical activities needed for life is released by the mitochondria in the form of ATP.
The highest power of x is 3, so this is a third degree multi-term expression, or polynomial. Thus, the answer is A.