What must a pitcher do to be in compliance while executing a pitch?

To be in compliance while executing a pitch, the pitcher must be in contact with the pitcher's rubber during the delivery of the pitch. This rule ensures that the pitcher has established a legal starting position before beginning their motion to pitch. By remaining in contact with the rubber, the pitcher demonstrates their intention to deliver the pitch while adhering to the established rules that govern pitching actions in baseball. Proper contact with the pitcher's rubber is a fundamental aspect of maintaining legality and consistency in baseball rules.

The other options do not align with the specific requirements set forth in the rules. Maintaining eye contact with the batter is not mandated and does not contribute to the legality of the pitch. Having a consistent arm angle or following the same delivery style as the last pitch, while potentially beneficial for a pitcher’s performance, is not a requirement of the rules themselves. Therefore, the emphasis on maintaining contact with the pitcher's rubber is the key compliance factor for executing a pitch.