Question

The main human activity that releases greenhouse gases is
using public transportation and there by reduce the affects of greenhouse gases
burning fossil fuels
texting on cellphones
eating meat

Answer 1

Answer: Burning Fossil Fuels

Explanation: Technically getting rid of anything on this list would reduce greenhouse gas emissions burning fossil fuel releases 50 billion tonnes of CO2e each year texting on cellphones is estimated to emit 32,000 tons CO2e per year and eating meat is estimated to emit 3.3 tons of greenhouse gas emissions.