Answer: (F): Be too cool or too hot.
Explanation: The Greenhouse Effect on Earth is a process of when gases in the atmosphere capture the heat produced by the Sun. Without the Greenhouse Effect, the heat reflected by Earth's surface would be lost in space. The temperature on Earth would drop drastically low and this could lead to oceans/lakes freezing over and some living organisms to die out. This would make most life incapable of living on Earth.