The app builder has two options available when defining an object-specific Create Record custom action:
Pre-Defining field values on the target object. This means that the app builder can specify default values for certain fields on the target object when creating a new record using the custom action.
Specifying the fields and layout of the action. This means that the app builder can choose which fields to include in the action and how they are arranged on the screen. Option B and D are not options available when defining an object-specific Create Record custom action.

Explanation
The app builder should consider two things before overriding standard buttons:
Standard buttons can be overridden with a Visualforce page. A Visualforce page is a web page that displays custom user interface elements using Visualforce markup and Apex code. A Visualforce page can be used to override a standard button and provide custom functionality or logic3.
Standard buttons that are not available for overrides can still be hidden on page layouts. A page layout is a layout that determines how fields, related lists, and buttons are arranged on a record detail or edit page. A page layout can be used to hide a standard button that cannot be overridden by removing it from the layout4. Option A and D are not things that the app builder should consider before overriding standard buttons.

Explanation/Reference: