Interesting question. I haven't a clue in this area of SQL Server, but it looked like a choice between option 1 and option 3 (option 4 had to be a joke - if it were that it would be famous, but it isn't famous so it isn't that; and option 2 seemed too silly for words). Option 1 was less bizarre, so I chose that and got it wrong.

The trouble is that even with the explanation and a bit of background reading, I still don't understand it; so obviously I have a lot more reading to do. I guess that means that this QoTD will result in a fair chunk of learning, so it must be a good question.