Final answer:
Flat files require the operating system to provide c. security, ensuring the protection of data from unauthorized access or alterations.
Step-by-step explanation:
When referring to flat files, these are simple data files that do not contain structured relationships like databases do. Flat files often rely on the operating system to handle the security and protection of the data contained within them. The correct answer to the question 'Flat files require the operating system to handle the protection of the data to provide what?' is security.
Security in this context involves the protection of data from unauthorized access or modifications, ensuring that only those with the correct permissions can access or alter the data. This can be contrasted with redundancy, which refers to the duplication of data to prevent data loss in case of a hardware failure, integrity, which ensures the accuracy and consistency of data over its entire lifecycle, and flexibility, which relates to the adaptability of the system or method used.