You’d better take the keys. It’s possible I’ll come home late. A. If I come home late, you’d better take the keys. B. You’d better take the keys in case I come home late. C. You'd better

If I come home late, you’d better take the keys.

You’d better take the keys in case I come home late.

You'd better take the keys as I possibly come home late.

I'll probably come home late so that you’d better take the keys.