Final answer:
The advantage of Indexed Sequential Access Method (ISAM) is that it enables both sequential and random access to data, making it versatile for various applications.
Step-by-step explanation:
The advantage of Indexed Sequential Access Method (ISAM) is that both sequential and random access can be used, depending on the situation and the user's needs. ISAM is a file management system that combines the sequential access of a sequential file with the direct access performance of an indexed file. It uses an index to quickly locate records, allowing for rapid random access, while still maintaining the capability for efficient sequential access through the data. This flexibility makes ISAM particularly useful for applications where both types of data access are required.