Read the following passage. which term correctly identifies the underlined sentence?

the telescope changed the way humans saw the universe. suddenly the stars and the planets seemed clearer and closer. galileo, an italian professor in the 1600s, wasn’t the first to invent the telescope, but he was the first to point his telescope to the sky and see the moons and planets clearly. galileo could see that the moon had a rough surface dotted with craters. he also found the milky way. galileo also observed that earth appeared to move around the sun instead of the other way around. his discoveries with the telescope caused curiosity about space that continues into modern times.

a.
topic
b.
main idea
c.
topic sentence
d.
supporting detail