Where will you be tomorrow, I said, in case I have to ring you?

• A. I asked where you will be the next day in case I will ring him.
• B. I asked where he would be the next day in case I had to ring him.
• C. I said to him where he will be in case I have to ring him.
• D. I enquired about his whereabouts the next day in case I would have to ring up.