Question

which is one advantage of using a reflecting telescope instead of a refracting telescope? reflecting telescopes are less expensive. reflecting telescopes produce clearer images. reflecting telescopes require only concave lenses. reflecting telescopes usually take up less space.

Explanation:

Refracting telescopes suffer from chromatic aberration (different colors of light focus at different points), which degrades image clarity. Reflecting telescopes use mirrors instead of lenses (so no chromatic aberration). Mirrors can be made larger (for better light - gathering) and are not limited by the problems of lens sag (in large lenses of refractors). So reflecting telescopes produce clearer images.
Reflecting telescopes are not necessarily less expensive. They require mirrors (not just concave lenses). And they don't usually take up less space (e.g., large - sized reflecting telescopes like the Hubble Space Telescope (a reflecting telescope) have a significant size).

Answer:

Reflecting telescopes produce clearer images.