A company has reference data stored in multiple custom metadata records that represent default information...

Comprehensi22ve and Detailed 150 to 250 words of Explanation:

This requirement involves two different automation triggers: record creation (insert) and record deletion (delete). To handle these events, Salesforce provides both declarative and programmatic options.

Flow Builder (Option B) is the preferred declarative tool. Record-Triggered Flows can be configured to run "Before" a record is saved to handle the default value assignment upon insertion. They can also be configured to run when a record is deleted. Using the "Custom Error" element within a Flow, an administrator can easily block a deletion and present a user-friendly error message if the contact belongs to a flagged region.

Apex Triggers (Option D) are the programmatic equivalent. A developer can write a before insert trigger to perform the metadata lookup and set field defaults, and a before delete trigger to check the region and call addError() on the record to prevent the deletion.

Options A (Remote Action) and C (Invocable Method) are not standalone automation triggers. A Remote Action is for JavaScript-to-Apex communication in Visualforce, and an Invocable Method is a piece of code called by another tool like a Flow or Strategy Builder. Therefore, Flow and Triggers are the two primary mechanisms to satisfy both the insertion and deletion requirements.

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