Question

How could you combine the following two sentences into a complex sentence with a dependent adjectival clause?

The boy wore a green coat. He carried his sister home.

A. The boy carried home his sister's green coat.
B. The boy wore a green coat, and he carried his sister home.
C. The boy who wore a green coat carried his sister home.
D. The boy wore a green coat; he carried his sister home.

I put C, but it's wrong.