Now that we've broken down the Template, we can look at the properties of the Dropdown component.
The parent Dropdown object has a Dropdown (TMP_Dropdown for TextMeshPro - Dropdown) component. It has all the properties common to the other interactable UI objects, along with a few that are exclusive to Dropdowns:
As you can see from the preceding image, the properties on the UI Dropdown and TextMeshPro - Dropdown are nearly identical. The only difference is the Text objects in are standard UI Text objects in the UI Dropdown and are TextMeshPro - Text objects in the TextMeshPro - Dropdown.
The Dropdown component is actually ...