A service uses an ALB with HTTP health checks. Instances accept client requests only when the Host header is app.example, so health checks fail. What is the most appropriate fix?

1. Add an app.example public DNS record and assume it rewrites health-check headers.
2. Change the target group to UDP while keeping the same ALB.
3. Disable health checks and send traffic to all registered targets permanently.
4. Provide a health endpoint that accepts the load balancer health-check request and configure its path.