A Splunk Job is essentially a search process that is initiated through a report or an alert. These jobs are also subjected to a usage quota, ensuring that resource allocation is managed effectively. Furthermore, each of these jobs runs as a child OS process that originates from the main Splunk daemon process, known as splunkd. Therefore, the correct answers include searches subjected to a usage quota, a search process initiated via a report or alert, and a child OS process from splunkd.