With two outs and runners on second base (R2) and third base (R3), the batter (B1) grounds to the shortstop. R2 runs toward the shortstop while the shortstop is fielding the ground ball. R2 then purposely steps right in front of the shortstop (not close enough to be tagged) as he throws to first base to attempt to retire B1. The shortstop's throw to first base skips past the first baseman. R3 and R2 score, while B1 ends up being thrown out as he attempted to advance to second base. Which of the following should the umpire do:

 

A) The umpire should not call "interference" on R2 because there was no contact and the shortstop was able to make a reasonable thrown to first base.

B) The umpire should call "interference" only if B1 is not retired by the throw to 1st base.

C) The umpire should call "interference" only if B1 is not retired at 2nd base.

D) The umpire should call "interference" immediately when he sees R2 actions.

 

What happens to R3, R2, and B1? How many runs score on this play?