George Stephenson was an engineer. He was the son of Robert Stephenson.
Which sentence combines the two sentences by making them a compound sentence?
A. George Stephenson was an engineer and the son of Robert Stephenson,
B. Although he was the son of Robert Stephenson, he was also an engineer,
C. George Stephenson was an engineer, and he was the son of Robert Stephenson,
D. Because he was the son of Robert Stephenson, he was an engineer,