How can setting data to read-only help protect it?

Setting data to read-only is an effective way to protect it primarily because it prevents accidental editing of that data. When data is marked as read-only, users can view the information but cannot modify, delete, or overwrite it. This is particularly important in situations where data integrity is crucial, such as in databases or critical documents, where unintentional changes could lead to errors, loss of information, or inconsistencies.

Other options do not correctly capture the function of read-only settings. While preventing any user from accessing the data is incorrect, read-only status means users can still access the data, just not modify it. Speeding up data retrieval is unrelated to its read-only status; the performance of data retrieval generally depends on the data structure or the efficiency of the database system, not on whether the data is editable or not. Unlimited access for modifications contradicts the very concept of setting data as read-only, as this would imply unrestricted editing capabilities, which read-only data explicitly denies.