Roles are named collections of privileges in Oracle databases.

A. False. Roles cannot be assigned to other roles using the ALTER ROLE statement.

B. False. Roles can be assigned to both users and other roles.

C. True. Roles are assigned to users using the ALTER USER statement, but this is not the only method.

D. True. A single role can be assigned to multiple users, simplifying the management of user privileges.

E. True. A single user can be assigned multiple roles.

F. False. Privileges are not assigned to a role using the ALTER ROLE statement.

G. True. Privileges are assigned to a role using the GRANT statement.