What is a Dashboard made of?

You can create a Lookup Relationship to link an object with itself.

Relative Dates in Report

An administrator needs to create a one-to-many relationship between two objects with
limited access to child records.
What type of field should the administrator use?

An administrator installed a managed package that contains a permission set group. The permission set group that was installed includes Delete access on several objects, and the administrator needs to prevent users in the permission set group from being able to delete records.
What should the administrator do to control Delete access?