What is an important philosophy in ensuring customers' needs are met under Total Quality Management tool?

a. It is the role of the marketing department to ensure customers' needs are met.

b. It is difficult to satisfy customers' needs so the company must conduct regular customer survey to find out their needs.

c. Every part of the organization plays an important role to ensure customer satisfaction

d. It is the responsibility of the team members of the TQM project team to introduce changes to meet customers' needs.