Your website runs on Compute Engine and marketing wants to test conversion rates between three designs. Which approach should you use?

The correct approach is to deploy the website on App Engine and use traffic splitting. App Engine's traffic splitting feature is designed precisely for A/B testing and canary deployments, allowing you to route different percentages of incoming requests to different versions of your application (in this case, the three website designs). This enables direct comparison of conversion rates. Deploying on App Engine as three separate services is incorrect because while it would host the designs, it doesn't inherently provide the traffic management needed for A/B testing; you'd need an additional load balancer or custom routing. Cloud Functions are serverless functions best suited for event-driven, short-lived tasks, not typically for hosting an entire website with continuous traffic, making both Cloud Functions options less suitable for this use case.