Which of the following best describes a ground rule double?
A: When 2 batters in a row hit doubles.
B: When a batter hits a double, and makes it to 2nd base before the defense can even get the ball to 2nd base.
C: When a batter hits a ball that lands in fair territory in the outfield, then bounces off the ground, and over the fence.
D: When a batter hits a ground ball that makes it past the infielders, and the batter is able to make it to 2nd base for the double.