The Earth's Average Temperature Appears to Be Slowly Increasing, and Heralds

The earth's average temperature appears to be slowly increasing, and heralds a new era in environmental challenges for numerous species. Most evidence supports the hypothesis that climatic change is the result of

A) invasive species that disrupt ecosystem services.
B) human activities that modify the atmosphere.
C) the disappearance of key plant species that affect the water cycle.
D) excess expansion of rainforests.