I always check the box that applies to the reason for the trip, but on my return from a business trip to Sweden last week, the immigration officer made me change it to pleasure. He said it may have been business on my way TO Sweden, but now I was coming HOME. It was the business trip from hell, flight reroutes due to weather, missed connections, luggage didn't arrive until days later both outbound and inbound, and I was just too tired to argue with him - but, really - how ridiculous was that!