Final answer:
The best example of self-serving bias among the given options would be Randy, who believes he works harder than others and is underappreciated.
Step-by-step explanation:
The best example of self-serving bias among the given options would be option (D) Randy, who believes he works harder than others and is underappreciated.
Self-serving bias is the tendency to explain our successes as due to internal characteristics but to explain our failures as due to external factors.
In this case, Randy is attributing his lack of appreciation to external factors, rather than considering the possibility that his efforts may not be as exceptional as he believes.