Answer:
A. Carbohydrate is a coumpound. Oxygen is an element.
Step-by-step explanation:
Carbohydrates are organic compounds that are organized as ring structures and are always composed of the elements carbon, hydrogen, and oxygen. Carbohydrates are truly hydrates of carbon because the ratio of hydrogen atoms to oxygen atoms is always nearly 2:1, as in H2O. Pure oxygen gas consists of molecules but it is still considered an element, rather than a compound, as the molecules are made up of a single type of element. Compounds are made up of one or more element.