Q: After A1 shoots the basketball from the elbow, the ball hits the rim with B4 defending. In the rebounding play, after the ball hits the rim, B4 uses their arms to try and prevent A1 from getting around to get the rebound. Is the official correct in calling a foul on this play?
A: Yes
FIBA Rule 33.9
It is legal for a player to extend his/her arm(s) or elbow(s) outside of his/her cylinder in taking a position on the court. Still, they must be moved inside his/her cylinder when an opponent attempts to pass by. if the arm(s) or elbows(s) are outside his/her cylinder and contact occurs, it is a blocking or holding call.