Which of the Following Is the Most Accurate Way to Evaluate

Which of the following is the most accurate way to evaluate a training program?

A) use only a pretest
B) conduct pretests,train only part of the employees,then compare the trained employees to the untrained
C) conduct pretests and posttests on all untrained employees
D) use only a posttest
E) check trainees' performance,knowledge,and attitudes only after they have completed the training program