Which statements are correct regarding indexes?

Which statements are correct regarding indexes? (Choose all that apply.)

A.
When a table is dropped, the corresponding indexes are automatically dropped

B.
A FOREIGN KEY constraint on a column in a table automatically creates a non unique
key

C.
For each data manipulation language (DML) operation performed, the corresponding

indexes are automatically updated.

D.
A nondeferrable PRIMARY KEY or UNIQUE KEY constraint in a table automatically
creates a unique index.