Question

why is the greenhouse effect essential for life on earth? it reduces the amount of sunlight reaching earth. it creates oxygen for humans to breathe. it prevents the earth from freezing. it increases the earths average temperature.

Explanation:

The greenhouse effect traps heat in the Earth's atmosphere. Without it, the Earth would be too cold (freezing) for most life forms. Photosynthesis (not the greenhouse effect) creates oxygen. The greenhouse effect's role in temperature regulation (preventing freezing) is key here.

Answer:

It prevents the Earth from freezing.