Which of the following is an advantage of using a database instead of a flat...

The CompTIA Tech+ Study Guide details this advantage:

“If you need to have multiple concurrent users accessing data, you need a database. Flat files don’t do well when several people try to access them at once. In the vast majority of cases, one user might be able to write to the file, but all users will be limited to a read-only copy.”

It further states:

“Databases generally lock only on a record level… so multiple people can actively use the database at one time.”

Therefore, the primary advantage of databases over flat files is support for multiple concurrent users.

Verified Reference:

Chapter 7: Database Fundamentals — “When to Use Databases” (pp. 389–391).