Which condition must be true for the pitcher to throw or feint to a base as an infielder?

• A. His pivot foot is on the ground clearly behind the pitcher's plate.
• B. His non-pivot foot is on the ground behind the pitcher's plate.
• C. Both feet are on the ground behind the pitcher's plate.
• D. He steps off the pitcher's plate in any direction or with either or both feet.

Answer: (A)

The move to a base from the pitcher’s mound must start with the pivot foot kept in contact with the pitcher's plate. That contact with the plate is what makes a throw or feint a legal pickoff move rather than a step-off or an illegal action. So the condition described—the pivot foot on the ground clearly behind the pitcher's plate—captures the requirement that the pivot foot remains on the plate during the feint or throw.

If the non-pivot foot were the only foot kept on the ground, or if both feet were on the ground behind the plate with no pivot foot in contact, or if the pitcher simply steps off the plate in any direction, the action wouldn’t meet the legal constraint for a base throw/feint.