bumping the defender before taking a shot

[ysong]

How do you call these plays:

B1 guards A1 near the basket, and maitains his legal guarding position.

a) when contact between A1 and B1 exists, A1 leans toward B1 to create separation before A1 takes a shot.

b)when no contact between A1 and B1, A1 initiates the contact by leaning (or crashing) into B1, before A1 takes a shot.

in both cases, the force is not big enough to knock B1 to the floor, but enough for A1 to gain a split of second uncontested time to make his shot.

c)both A1 and B1 jump up without contact, when still in the air, A1 twists his body to initiates the contact and crashes into B1, before A1 release the shot.


Do you call it offensive fouls on these cases?