1.) when the greenhouse effect is exaggerated through human activities more and more heat will be trapped on the earth, increasing the average temperature. what is this called? a.) global cooling b.) global warming c.) photosynthesis d.) co2 emissions 2.) what is the largest source of u. s. greenhouse gas emissions? a.) agriculture b.) transportation c.) electricity production d.) home heating 3.) what is an example of the greenhouse effect? a.) steam rising from boiling water b.) baking brownies on a metal pan. c.) stepping on hot pavement and it burning your feet. d.) inside of a car becoming hot on a warm day. 4.) what are the two most major gases produced by people? a.) methane and fluorine b.) carbon dioxide and methane c.) carbon dioxide and nitrous oxide d.) methane and nitrous oxide