Fact 1: Agreenhouse is used to protect plants by keeping them warm. Fact 2: Plants are Earth's producers. Given the two facts above, what is used to protect producers and keep them warm?

Pick from: A. an electric stove. B. sweaters. C. green houses. D. dirt. E. animal fur. F. In the winter. G. evaporation. H. plant fans.
The answer is:
C.