I would not do option A unless you are reaaaaally sure it will be OK. It would be a nightmare for a lot of people not to have the opportunity to plan/organize/etc. before a vacation. Both in terms of work (getting people to cover for you, finishing a project, etc.) and in terms of home (packing, figuring out what the weather will be and what clothes are needed, making sure they have no appointments that week, etc.). Maybe you could compromise if you wanted to surprise her, and say: I'm taking you on a trip on such-and-such days, but it's going to be a surprise. Pack for such-and-such climate with lots of city walking and one fancy dinner out (except fill in whatever you have planned, obviously).
I did once surprise a good friend with a 2-night weekend trip, but it didn't involve time off work, and I had his husband planning ahead for weeks (packed him a bag, made arrangements to get to the airport, etc.). I only did it as a surprise because his husband suggested it and thought he would love it. It was a great time and a very special trip in retrospect, although I'm sure he would never dream of telling me that it was inconvenient or annoying that I bought him a plane ticket, so who knows what he was really thinking that day on the plane :-P