Component Testing — quiz

A QA engineer is writing a component test for an Order Service. The Order Service calls a Payment Service via HTTP and writes to a PostgreSQL database. Which setup correctly defines the component test boundary?

• Run the Order Service, Payment Service, and a real PostgreSQL instance all together
• Run only the Order Service, replace the Payment Service with an HTTP stub (e.g. WireMock), and use a real or containerised PostgreSQL database
• Mock both the Payment Service and PostgreSQL with in-memory fakes at the code level
• Test the Order Service only at the unit level, not at the service process level