Riley has worked for Centrum Springs, Inc., for many years and has now been given the opportunity to advance in the company. His manager is retiring and hopes that Riley will take over for him. However, even though Riley is an experienced employee, there are many things that he still needs to learn. Riley has trained many new employees, but he has never held a management position. Riley needs to have a general understanding of what it takes to be a manager. There are many problems in Riley's department. There are no plans to fall back on in case the initial plan fails. Riley also will need to learn how to direct people in such a way that makes them want to do more than they absolutely have to. Riley feels that this is a great opportunity, and he is anxious to learn everything to be a great manager. He knows that if he performs well in this position, he will have the opportunity to move up the corporate ladder. Refer to Centrum Springs, Inc. Riley's usual duties represent which of these areas?

a. Financial management
b. Operations management
c. Marketing management
d. Human resources management
e. Administrative management