What is the log file used for storing syslog messages related to scheduled jobs?

The correct choice is based on the standard logging practices in Unix-like systems for scheduled jobs managed by the cron daemon. The log file located at /var/log/cron specifically records entries related to the scheduling and execution of cron jobs. This includes various information, such as when a cron job was triggered, whether it executed successfully, and any errors that may have occurred during execution.

Using /var/log/cron is a convention in many Linux distributions and is vital for system administrators to monitor and debug scheduled tasks. The other options do not represent standard logs for cron jobs on most systems; thus they would not typically provide the information needed for tracking scheduled tasks.