Step 1: Concept
Schedule M of the Drugs and Cosmetics Rules describes Good Manufacturing Practices (GMP) and requirements of factory premises.
Step 2: Meaning
Schedule M is subdivided to address different product categories like pharmaceuticals, cosmetics, and medical devices.
Step 3: Analysis
Schedule M covers drugs, and Schedule MII covers cosmetics. Schedule MIII is specifically dedicated to the GMP and factory requirements for medical devices.
Step 4: Conclusion
Hence, Schedule MIII is the correct classification for medical devices.
Final Answer: (C)