Gretel Wants to Be as Accurate and Fair as She

Gretel wants to be as accurate and fair as she can when evaluating her subordinates. Which of the following would help her be both accurate and fair in her evaluations?

A) Gretel has her employees evaluate themselves and then observes them on repeated occasions, rating their performance on a numerical scale.
B) Gretel receives training on the biases of social perception and gives her subordinates clear performance standards.
C) Gretel remains detached from her employees and is the sole evaluator.
D) Gretel has several raters assess her subordinates and then gives the employees feedback without using due process in her appraisal.