Why did coal replace wood as a fuel source?
A - Coal was a cleaner fuel source than wood
B - There was a lot of coal available and it required less work to mine than cutting wood
C - Coal was used to make steel, which was used in the manufacturing of ships
D - Too many trees were being cut down and the environment needed to be preserved
Answer: B - There was a lot of coal available and it required less work to mine than cutting wood