Why are human alterations to the carbon cycle a problem? (Human alterations being fossil fuels, consuming plants and animals, and breathing.)

Burning fossil fuels, changing land use, and using limestone to make concrete all transfer significant quantities of carbon into the atmosphere.

the answer is a. now keep my answer here.

endo:

regulates body hormones, aldosterone, vasopressin

neural:

signal, regulates body using electric signals, reflex

endo has to do with hormones; aldosterone and vasopressin are both hormones. i also had this question and got it right : d