How can you make an optional field mandatory for user input? There are 2 correct answers to this question.

How can you make an optional field mandatory for user input? There are 2 correct answers to this question.
A . Adjust the change request customizing for the corresponding field to mandatory.
B . Implement a custom validation (for example via ABAP or Business Rule Framework plus) on the corresponding field.
C . Change the display settings of the field in the UI configuration.
D . Adjust the data model by selecting the required check box for the corresponding field.

Answer: B,D