Which statement correctly describes a difference between JMS and VM?

• A. VM supports publish-subscribe
• B. VM is external to the Mule runtime
• C. JMS is expensive
• D. VM queues require external brokers

Answer: (C)

The key idea is where the messaging infrastructure runs. JMS relies on an external broker outside the Mule runtime, while VM is an in‑memory transport that lives inside the Mule runtime itself, with no external broker. Because JMS requires you to deploy and manage a separate broker (licensing, hardware, maintenance, connectivity), it generally adds cost and complexity. VM, on the other hand, uses in‑memory queues inside Mule, so there’s no external broker to license or manage, making it cheaper and faster for intra‑application messaging.

The other statements aren’t the distinguishing factor here: the VM transport isn’t external to Mule, and VM queues don’t require external brokers. Pub‑sub behavior exists in JMS by design, while VM handles messaging within the Mule runtime, but the primary difference highlighted is the external broker versus in‑memory, internal nature.