Which discipline of Earth and space science is concerned with the study of the planets and stars? astronomy biology geology oceanography

Astronomy is concerned with planets, stars, and the physical universe as a whole. The root comes from the Greek word astronomos, meaning star-arranging.

Biology is concerned with living things. Geology deals with the earth's physical structure and properties. Oceanography covers the properties of the oceans. So it can't be any of these.

It must be A.