What is the difference between centripetal and centrifugal force?
Two of the given answers - choices (2) and (3) - are correct in different reference systems. It depends on the reference system of the observer:


In a non-accelerated reference system, centrifugal forces do not exist. Increasing angle of attack increases the centripetal force, that increases the turn rate. The reaction force of the centripetal force is the innate force of the plane.
A passenger in the plane observes the scenario from within an accelerated reference system. The plane is turning without obvious reason. The passenger's body wants to move in a straight line and seems to exert a force on the seat. This virtual force is called centrifugal. The seat seems to react by supporting the body with the same amount of force. When the pilot increases the angle of attack of the balanced turn, the centrifugal force will increase. The observer inside the rotating system is not aware of the centripetal force. The centripetal force does not exist for him.


Centripetal and centrifugal forces never co-exist in the same reference system! Even though they might appear like counter forces to each other, they should not be understood like that.

Centrifugal force is a construct to explain our perception and sometimes to simplify calculations in rotating reference systems.

Between the two, centripetal force is the more fundamental notion. It really describes what is going on, therefore (2) is the better answer from a scientific point of view. Nevertheless, (3) centrifugal force is a valid answer if the reference to a rotating system is established. That seems to be the case in the question. The centrifugal force describes what an occupant feels who is not aware of the rotation.