Which sentence is punctuated correctly?

A. The swim meet starts in an hour-- we need to hurry!
B. I have snacks, a bottle of water-- and a towel in my bag.
C. My swim meet was canceled because of rain... but it will be rescheduled.
D. Which bus do we take to the pool...

C. My swim meet was canceled because of rain... but it will be rescheduled.