Out of all of the other choices, the sunny beach seems most relaxing. When you arrive, you have only a surfboard and a single piece of luggage. The beach house you've been provided is in a private, secluded stretch of beach. There's little more else to do here than maybe go to town to fill the fridge, or just enjoying the amenities. The town isn't going anywhere, after all, but since you don't have a vehicle it's a bit of a hike.
A few activities stand out immediately as enticing to you.