Carbon dioxide is primarily used as an attractant in which type of traps?

The CDC Mini light trap is designed to attract mosquitoes and other flying insects using a combination of light and carbon dioxide. This trap mimics the visual and chemical cues that mosquitoes use to locate hosts; the carbon dioxide simulates the breath of potential hosts, making it particularly effective at drawing in target species.

Carbon dioxide traps specifically focus on this gas as the primary attractant, but the CDC Mini light trap utilizes both light and CO2, enhancing its overall effectiveness. The window screen trap does not employ carbon dioxide as an attractant, and while sticky traps can capture insects, they generally do not use attractants like CO2 to lure them in. Thus, the design and functionality of the CDC Mini light trap make it the correct choice for this question.