The correct answer is option 2, "trapping of solar energy due to carbon dioxide gases". The green house effect refers to the phenomenon where certain gases in the Earth`s atmosphere, such as carbon dioxide, trap solar radiation and prevent it from escaping back into space. These gases act like the glass walls of a greenhouse, allowing sunlight to enter but trapping the heat inside. This process is essential for maintaining a habitable temperature on Earth, as without the greenhouse effect, the average surface temperature would be much colder. However, an excessive increase in greenhouse gases, such as due to human activities, can lead to an enhanced greenhouse effect and global warming. Thus, the green house effect is the trapping of solar energy by certain gases in the atmosphere, primarily carbon dioxide.