Which file access method is suitable for databases where frequent reading and writing occur?

The chosen answer, indexed file access, is particularly suitable for databases that experience frequent reading and writing because it allows for efficient data retrieval and updates. This method employs an index structure that enables quick lookups, meaning that when a record needs to be read or modified, the system can locate it without scanning the entire file. This efficiency greatly reduces the time and resources required for operations compared to methods that require sequentially examining each record.

Indexed file access supports complex queries and allows for faster response times, which is essential in environments where the volume of transactions and data interactions is high. This ability to index certain fields in a database accelerates both search and write operations, making it preferable in data-intensive applications.

In contrast, sequential file access processes data in a linear fashion, which can lead to slower performance when frequent updates or reads are necessary. Likewise, direct file access, although capable of fast retrieval for known addresses, may not efficiently handle the dynamic nature of frequent changes. Graph access is generally used in more specialized contexts, such as for representing relationships rather than for managing general database transactional data. Therefore, indexed file access emerges as the most effective choice for scenarios involving frequent reading and writing.