What is the BEST way to revise this sentence so that it conveys clear, concise ideas and does not change the meaning of the sentence?

I rang the doorbell, but no one came to the door, and I was sure that this was the right address, so I waited, and then I saw a curtain move.

A. I rang the doorbell, and I saw a curtain move upstairs.
B. The curtains moved in the window the moment I rang the doorbell.
C. I was sure I was at the right address, but no one came when I rang the bell.
D. I rang the doorbell, but no one came to the door. I was sure this was the right address. While I waited, I saw a curtain move.