This question is testing the classic Salesforce Process Builder automation best practice , not a generic Flow-only rule. Salesforce’s official process design guidance states that an org should have only one record-change process per object . The reason is simple: every time a record is created or updated, Salesforce evaluates the record-change processes for that object. If an object has multiple record-change processes, the automation becomes harder to predict, harder to troubleshoot, and more likely to hit governor limits. Salesforce specifically explains that consolidating automation into one record-change process gives admins a single view of all criteria and actions for that object, reduces duplicated automation overhead, and allows the app builder to control the order of criteria evaluation.

A is not the best exam answer here. In modern Flow architecture, “one Flow per object” is often discussed as a design pattern, but it is not the exact best-practice wording being tested by this Platform App Builder-style question. Salesforce Flow design is more nuanced today because record-triggered flows can vary by trigger timing and event. B is wrong because validation rules should be separated by validation requirement, not forced into one rule per object. C is wrong because invocable processes are reusable modular processes, not the main record-change automation container.