Choices: 1). Heat energy. 2). carbon dioxide. 3). kinetic energy. 4). lowered energy cost. 5). sunlight. 6). oxygen. 7). climate. 8). water.

Fact 1: Using renewable resources to generate power reduces greenhouse gases. Fact 2: Carbon dioxide is a greenhouse gas. Given the two facts above, what does using renewable resources to generate power reduce?
Answer:
2).