Which of the following objects must you create?

You developed an ABAP managed database procedure (AMDP). You want to allow the enhancement of this AMDP using business add-in (BADI).

Which of the following objects must you create? There are 3 correct answers to this question.
A . A BADI definition
B . A BADI fallback implementation
C . An enhancement spot
D . A database procedure
E . A BADI simple implementation

Answer: A,B,C