Your organization has a 3-tier web application deployed in the same Virtual Private Cloud (VPC) network on Google Cloud Platform (GCP). The application consists of a web tier, an API tier, and a database tier. Each tier can independently scale in response to varying workloads. The design requires that network traffic flows from the web tier to the API tier and then to the database tier while ensuring that no direct traffic flows from the web tier to the database tier. How should you configure the network to meet these requirements?