12. 다음 두 문장을 한 문장으로 고칠 때, 빈칸 (A), (B)에 들어갈 말로 가장 적절한 것은?
This is the house. I live in the house.
→ This is the house (A)__________ I live in.
→ This is the house that I live in.
→ This is the house I live in.
→ This is the house (B)__________ I live.