Q: Fact 1: Burning fossil fuels increases the carbon in the atmosphere. Fact 2: The atmosphere is mostly carbon dioxide . Given the two facts above, what is the increased by burning fossil fuels?

Choices:
(I) fossils;
(II) Pollution;
(III) carbon dioxide;
(IV) ions;
(V) Greenhouse gases;
(VI) kinetic energy;
(VII) air;
(VIII) heat energy;
The answer is:
(III)