Syslog is the most appropriate log type to review for troubleshooting device behavior, such as unexpected reboots, as it provides a record of system notifications and error messages from network devices. Traffic logs, while helpful for understanding the data flow through the device, would not typically contain information about system stability or reboots. Audit logs focus more on security-relevant events, such as configuration changes and user access, rather than system status and error messages. Lastly, send/receive traffic statistics offer insights into the amount of data passing through the interface but would not provide information on why a device is rebooting.