Implement a highly available VPN (99.99%) between your project and a partner’s project across us-west1 and us-east1 with minimal infrastructure.

The correct option provides a highly available VPN (99.99%) with minimal infrastructure. HA VPN requires two tunnels from a single HA VPN gateway to the peer gateway. Deploying one Cloud Router and one HA VPN gateway in a single region for each VPC, then connecting them with two tunnels, establishes redundancy. Enabling global dynamic routing allows prefixes from both regions to be exchanged. The first option is incorrect because it suggests deploying infrastructure in both regions, which is not minimal. The OpenVPN options are incorrect because they introduce third-party software, which is not Google Cloud's native HA VPN solution and adds management overhead.