Which activity would reduce human sources of greenhouse gases? Increasing the size of livestock herds Monitoring worldwide volcanic activity Using wind energy to generate electricity Researching ways to add methane to the atmosphere

The answer is "using wind energy to generate electricity".

Explanation:

The Wind turbines may not emit water or sulfur compounds (with rare exceptions) and require no water as a coolant. The cost of power produced from energy sources may also be reduced by windmills, which will result in lower overall air quality and hosing pollution, that's why Utilizing wind energy for energy production decreases human greenhouse gas sources.