What is a possible result of an increased amount of CO2 in the atmosphere?

There are no options to this question, however, it can be answered using general knowledge. The answer is GLOBAL WARMING

Explanation:

Carbon dioxide, commonly called CO2, is one of the gaseous constituent of air. It is considered to be the most important greenhouse gas i.e. gases that have the ability to trap heat from the surrounding atmosphere. Due to this ability, CO2 in addition to other gases like methane are known to contribute to a phenomenon called GLOBAL WARMING.

GLOBAL WARMING is an increase in the atmospheric temperature of the Earth due to the effect of greenhouse gases. Global warming is a concern for the world populace, hence, an increase in the concentration of gases like CO2 in the atmosphere will lead to GLOBAL WARMING (an increase in Earth's atmospheric temperature).