Where are the components of the client tier of the ORA UI logical architecture hosted?

Where are the components of the client tier of the ORA UI logical architecture hosted?

A.
on the transcoding engine

B.
on the web server

C.
on the display device

D.
some components on the web server and some on the display device

Explanation:
The Client Tier is hosted on the display device, this may be a browser or an thick
client specific to the display device

Reference: Oracle Reference Architecture, User Interaction, Release 3.0