Explanation
The best options to implement for a public cloud solution for an existing application using lift and shift that requires scalability and external access are a load balancer and a VPN (virtual private network). A load balancer is a device or service that distributes incoming traffic across multiple servers or instances based on various criteria, such as availability, capacity, or performance. A load balancer can improve scalability by balancing the workload and optimizing resource utilization. A VPN is a technology that creates a secure and encrypted connection over a public network, such as the internet. A VPN can provide external access by allowing remote users or sites to connect to the cloud resources as if they were on the same private network.
Reference: CompTIA Cloud+ Certification Exam Objectives, Domain 1.0 Configuration and Deployment, Objective 1.4 Given a scenario, execute a provided deployment plan.