Answer:
D. centralized
Explanation:
Centralized design is a type of computing architecture where all or most of the processing/computing is performed on a central server. Centralized computing enables the deployment of all of a central server's computing resources, administration and management. The central server, in turn, is responsible for delivering application logic, processing and providing computing resources to the attached client machines.
Therefore in centralized design, the remote user’s keystrokes are transmitted to the mainframe, which responds by sending screen output back to the user’s screen