Which of the following best describes the two-tier database architecture?

A.
The user accesses a database server using a terminal.

B.
The user interface, data-processing logic, database access and data validation functions are performed on a mainframe server.

C.
The user interface and data validation functions are performed by the client whereas the data- processing logic is performed on a server.

D.
The user interface and data-processing logic are performed by the client whereas the server handles database access and data validation functions.