The onset of puberty and the onset of menopause are examples of age.

Biological  age.

Explanation:

Your biological age is that based on the quality of your body. It is the set of conditions of your biological device. It is related to the aging of cells and is a consequence of physical and mental habits and defines their quality of life. It is defined by your mood, health, disposition, etc. The biological age is also defined by the common physiological changes in the human organism, an example of this is puberty and the onset of menopause.

it's c. (to reduce the greenhouse effect/carbon gasses)