With one out and a runner on 3rd base (R3), the batter (B1) hits a high fly ball right over home plate. The catcher positions himself for the catch while the home plate umpire positions himself to determine fair/foul and to watch the play. However, the umpire gets too close to the catcher and the catcher runs into the umpire and the catcher falls down. The ball lands and settles in fair territory. R3 scores and B1 ends up on 2nd base. The umpire clearly got in the way, so what is the call:

 

A. The umpire interfered, so B1 is out and R3 is returned to 3rd base

B. The umpire interfered, so B1 is out but R3 scores

C. This is not umpire interference, but B1 remains at bat and R3 is returned to 3rd base

D. This is not umpire interference, so play on -- R3 scores and B1 remains at 2nd base