Which directory contains files that are variable, meaning they change constantly, such as database files and log files?

• A. /tmp
• B. /usr
• C. /var
• D. /etc

Answer: (C)

Variable data refers to files that grow or change as the system runs—logs, databases, caches, and similar ongoing state. The directory designed for this kind of data is /var. It contains subdirectories like /var/log for logs, /var/lib for application state such as databases, and /var/cache for cached data. These files reflect activity and persistence over time, which is why database and log files belong here. In contrast, /tmp is meant for ephemeral temporary files, /usr holds mostly static program files, and /etc stores configuration data that isn’t the ongoing dynamic data the system generates.