​Which of the following is TRUE about firms organized along functional lines?

A) ​Workers find it difficult to develop functional expertise
B) Workers find it difficult to share information within their division
C) They foster the exploitation of economies of scale
D) ​All of the above

Firms organized along functional lines are structured around specialized areas, such as marketing, operations, and finance. This allows them to exploit economies of scale by consolidating resources and expertise in each area, resulting in cost savings and efficiency. While there may be some challenges with information sharing and developing expertise, these are not generally considered significant drawbacks of the functional structure. Therefore, the correct answer is C.