$20.$ Which statements are true of a recursive method?

Multiple$-$choice options $($select one or more$)$:

A$.$

There must be a base case which causes the method to complete.

B$.$

There must be movement towards the base case as the algorithm, method progresses.

C$.$

Recursion is always the best solution to any problem.

D$.$

The method must call itself.

E$.$

The method must never call itself.