Darrell is a clothier whose company, 24-7 Activewear, has separate product lines for men, women, and children. He has grouped his organization into different departments such as production, marketing, and finance. Most of the employees report to two managers a departmental head and a divisional head. Darrell encourages lower-level managers to make important decisions in order to promote quick and effective decision making. It can be inferred that Darrell's firm utilizes the approach to departmentalization.

a. geographical
b. product
c. vertical
d. matrix
e. conglomerate