✅ Correct Answer: C. After update Trigger
🔍 Explanation:
The question asks for the most customizable approach to create a new record after another is updated, using data from the updated source object.

✅ Why "After Update Trigger" is the Most Customizable:
Triggers provide full control over:

The timing of execution (before vs after)

Complex conditions

Cross-object logic

Multiple record operations in bulk

In an after update trigger, the original record is already committed, so you can:

Safely reference its ID

Create related records using its final data state

I don't agree with this answer. If it is process builder, then why not flows, they are most extensive in nature than process builder. But even after that why not triggers since we are talking about the customizable approaches?