The word underlined in the sentence above is best defined as
a.
flat areas that are cut into the side of hills and used to grow crops
b.
rice terraces that usually are carved on the side of a mountain
c.
ridges that surround and keep water in irrigated areas
d.
the spreading of something from one place to another

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.