○ 正解です。

For questions using "Do you mind _______?" a "No" answer means "いいよ" and a "Yes" answer means "だめ"

For example :

1. "Do you mind if I use your toilet?"

"No, go ahead." (使っていいよ)

2. "Do you mind if I smoke?"

"I'm sorry but this is a non-smoking house." (ごめんね。吸わないでください。)