When screening behind a stationary opponent, what must the screener do?

The requirement when screening behind a stationary opponent is to allow the opponent to take a step backward. This is in line with the principles of legal screening, which prioritize the safety and fair play of all players on the court. The screener must provide enough space for the defender to move and not impede their ability to react or move effectively.

By allowing the opponent to step back, the screener ensures they are not creating an unfair advantage or engaging in illegal contact that could result in a foul. This requirement emphasizes the importance of maintaining a certain level of respect for the movement and space of the opposing player during gameplay.

The other choices involve either obstructive actions or contact that could violate the rules of legal screening. The emphasis is on creating a proper screening situation without impeding the defender's natural movements or causing foul play.