20. The ANSI/SPARC has established a three-level architecture for a DBMS:conceptual, external, and internal. Which of the following is true?
(A) The conceptual level defines the low-level access methods and how bytes aretransferred.
(B) The conceptual level interacts directly with the users.
(C) The internal level determines where data is actually stored on the storagedevices.
(D) The external level interacts directly with the hardware. The data model isdefined on this level, and the main functions of the DBMS are also on thislevel.
(E) The external level is an intermediary and frees users from dealing with theinternal level.