On Which Part of the Carbon Cycle Have Humans Had

On which part of the carbon cycle have humans had the GREATEST impact?

A) return of CO₂ to the atmosphere by oxidation of ancient organic matter
B) capture of atmospheric CO₂ by chemical weathering of rocks
C) storage of CO₂ through biomineralization in the oceans
D) deposition of organic carbon in deep-sea sediments
E) All of these choices are correct.