What would most likely happen to the carbon cycle if there were no more plants on Earth?

Animals would consume more carbon.

More carbon would be released from fossil fuels.

Carbon would build up in the atmosphere.

Animals would perform more photosynthesis.

Plants use carbon to live, just like humans use oxygen. It's a virtuous cycle sine humans breathe oxygen and expel carbon, and plants "breathe" carbon and expel oxygen.

If plants weren't there to "breathe" the carbon, it would just sit in the world, and build up in the atmosphere.

The answer would be (c) Carbon would build up in the atmosphere.