A Salesforce associate wants to quickly create an org where they can learn, practice, and...

 The type of org that the associate should create from within Trailhead to quickly learn, practice, and develop Salesforce skills is a Playground. A Playground is a free, fully functional Salesforce org that you can use to test and explore the platform. You can create multiple Playgrounds from Trailhead and use them to complete hands-on challenges and projects1. A Developer Edition is a type of org that you can create from the Salesforce website, not from Trailhead. A Sandbox is a type of org that you can create from a production org as a copy of it for testing and development purposes