A company captures orders and needs to send them to the Order fulfillment system.

When designing an integration where the user does not require immediate confirmation, the architect is moving away from a synchronous "Request-Reply" pattern toward an asynchronous "Fire-and-Forget"16 or "Batch Processing" pattern. In such scenarios, the most critical architectural constraint is defining the latency requirements.

Latency dictates the technical choice of the integration tool. If the fulfillment system needs the order within seconds of creation to begin a high-speed picking process, the architect might choose Salesforce Outbound Messaging or an Apex Callout triggered by a Platform Event. If the system only needs to process orders once an hour or overnight, a Batch ETL process is more appropriate. Understanding the acceptable delay (latency) ensures that the solution meets business expectations without over-engineering for real-time performance where it isn't required.

While Option B (Outbound Messaging) is a valid technical capability, it is a specific solution rather than a high-level "system constraint question" that drives the initial design phase. Option C (Address Validation) is a functional requirement regarding data integrity, but it does not define the architectural framework of the integration as effectively as latency does. By identifying the latency threshold, the architect can determine if the integration should be near real-time, hourly, or daily, which in turn influences how the system handles error recovery, retries, and transaction volumes.