ITS B. WORKFLOW.

🧠 Why Workflow Might Still Be Suggested:
Outbound Messages + Time-Based Actions Workflow remains the only declarative tool that supports outbound messages with time delays (like "notify an external system one day later") without using Apex or invocable custom Flow actions.

Exam Context vs. Real-World Best Practice For the Platform App Builder exam, Salesforce wants you to know how to use tools based on their native capabilities—not just what’s future-forward. So Workflow often pops up as the “correct” answer even if Flow is the preferred tool going forward

B or C

@Ess Process builder can't send an outbound message, so going by your logic, it would be workflow, but I would choose Flow instead as the correct answer.

Why would Process Builder be the best answer in the APP-Builder exam?

For the APP-Builder exam, Salesforce evaluates knowledge of automation tools such as Workflow, Process Builder, and Flow within their functional context, not necessarily based on current best practices.

If we consider the exam's effectiveness criteria:

It needs to update a field on the Lift object → Process Builder can do this. ✅
It needs to schedule an action for the next day → Process Builder has "Scheduled Actions" that make this easy. ✅
It needs to send an Outbound Message → Process Builder supports this directly. ✅
Although Flow can also achieve these tasks, Process Builder is the most direct and effective answer in the context of the exam, as it is specifically designed to handle this type of automation without requiring more advanced logic.

Correct: C
Process Builders and Workflow Rules will no longer be supported by salesforce starting 31 Dec, 2025. So it's not recommended to implement new, actually is recommended to migrate to Flow.
Source: https://help.salesforce.com/s/articleView?id=001096524&type=1