Final answer:
The typical file used to specify proxy settings for private synthetic monitoring is configuration.yaml, which includes details like the proxy URL and authentication.
Step-by-step explanation:
In the context of configuring a proxy for private synthetic monitoring, the file typically used to specify proxy settings is configuration.yaml. This YAML (Yet Another Markup Language) file is often utilized to define configuration settings in a format that is both human-readable and can be easily processed by systems. Proxy settings in a configuration.yaml might include the proxy URL, port, and any required authentication details. These settings instruct the synthetic monitoring tool how to route its traffic through the specified proxy server.