Answer:
Enzymes help speed up chemical reactions in the human body. They bind to molecules and alter them in specific ways. They are essential for respiration, digesting food, muscle and nerve function, among thousands of other roles.
Explanation:
Because they are prokaryotic cells.
Alternative energy sources are those that do not deplete natural resources and do not harm the environment.
Options A, B, and C are all fossil fuels, which we know can be depleted and harm the environment.
The only valid option here is D, Geothermal energy.
Geothermal energy is both renewable and environmentally friendly.