29. It's too bad you didn't tell me you had a spare ticket for the show! Which of the following is the correct transformation of the original sentence?

A、Ifonlyyoudidn'ttellmeyouhadaspareticketfortheshow!
B、Onlyifyoutoldmeyouhadaspareticketfortheshow!
C、Onlyifyoudidn'ttellmeyouhadaspareticketfortheshow!
D、Ifonlyyouhadtoldmeyouhadaspareticketfortheshow!