Did you know the roller skate has been around since early 1700s? people who loved winter ice-skating wanted to go "dry land skating" in the summer, and so they attached wheels to their boots. the early models were hards to roll, though. in the late 1800s, roller-skate design improved. once the skaters were easier to handle, he sport became more popular.

which of these best states the main idea of the passage?

a) people liked ice-skating in the winter
b) many people wanted to skate in the summer.
c) roller-skating has become a popular sport over time
d) early roller skates were difficult to use