Which of the Following Is a Guideline for the HCI

Which of the following is a guideline for the HCI approach to system design?

A) Design with prototyping to accommodate the average employee, considering that all employees will receive the same training.
B) Examine the software used and consider the fit between the human and the computer.
C) Identify what obstacles exist for users in their attempts to accomplish their assigned tasks.
D) Examine the actual usefulness and perceived usefulness from post-implementation evaluation surveys.