Nice question. What is most interesting to me is why 23% (as of now) got it wrong.

I can see thinking that

select dateadd( ss, -1, datediff(yy, 0, @ThisDate) + 1 )

is the correct answer if you don't know that the year "0" is 1900. But, I don't see how you can know how to interpret parenthesis and still choose C or D.

Hope everyone has a great 2014! Our most eastern members are already there.