—Morgan, could you tell me _____________?

—In the Mexican city of Cancun.

—Morgan, could you tell me _____________?
—In the Mexican city of Cancun.

—Morgan, could you tell me _____________?

—In the Mexican city of Cancun.

1. A.
   where did the UN Climate Change Meeting open
2. B.
   when did the UN Climate Change Meeting open
3. C.
   when the UN Climate Change Meeting opened
4. D.
   where the UN Climate Change Meeting opened