Which two human activities are believed to be the greatest contributors to global warming?

Question

nonnative species introduction and the burning of fossil fuels
deforestation and the burning of fossil fuels
deforestation and nonnative species introduction
non-sustainable harvesting and nonnative species introduction

Answer 1

The two human activities believed to be the greatest contributors to global warming are deforestation and the burning of fossil fuels. These activities significantly increase the concentration of greenhouse gases in the atmosphere, leading to climate change.