You are a developer that works for a local concert venue. Customers use your company’s website to purchase tickets for events. You need to provide customers with immediate confirmation when a selected seat has been reserved. How should you design the ticket ordering process?

A. Upload the seat reservation to a Cloud Storage bucket, which triggers an event to the backend service that processes the seat reservation. B. Submit the seat reservation in an HTTP POST request to an Application Load Balancer. Configure the Application Load Balancer to distribute the request to the backend service that processes the seat reservation. C. Add the seat reservation to a Cloud Tasks queue, which triggers Workflows to process the seat reservation. D. Publish the seat reservation to a Pub/Sub topic. Configure the backend service to subscribe to the topic to process the seat reservation.