Explanation
Containers are a type of deployment technology that packages an application and its dependencies into a lightweight and portable unit that can run on any platform or environment. Containers can help deploy a single application that has different versions in an existing IaaS instance, as they can isolate and run multiple versions of the same application without any conflicts or interference. Containers can also enable faster and easier deployment, scaling, and management of cloud-based applications. References: CompTIA Cloud+ Certification Exam Objectives, page 11, section 1.6

Explanation
The technology that provides the most portability for a multicloud environment is containers. Containers are units of software that package an application and its dependencies into a standardized and isolated environment that can run on any platform or cloud service. Containers are lightweight, scalable, and portable, as they do not depend on the underlying infrastructure or operating system. Containers can also be managed by orchestration tools that automate the deployment, scaling, and networking of containerized applications across multiple clouds. Reference: [CompTIA Cloud+ Certification Exam Objectives], Domain 1.0 Configuration and Deployment, Objective 1.3 Given a scenario involving integration between multiple cloud environments, select an appropriate solution design.

Explanation
A snapshot is an image of your system/volume at a specific point in time. It captures the entire file system as it was when the snapshot was taken. When a snapshot is used to restore the system, the system will revert to exactly how it was at the time of the snapshot1. Snapshots are designed for short-term storage and fast recovery. They do not need a lot of storage space or time to create copies234.
Taking a snapshot of the system before the OS upgrade would ensure the fastest recovery of the system in case the upgrade fails in an unrecoverable way. The administrator could simply restore the system from the snapshot and avoid any data loss or corruption. This would be much faster and easier than performing a full backup or testing the upgrade in a preproduction environment.

Explanation
The best solution to simplify management of a more complex DNS and DHCP environment for a company that has grown over the last couple of years is IPAM (IP address management). IPAM is a tool or service that allows centralized management and automation of DNS and DHCP functions, such as IP address allocation, reservation, release, or renewal, as well as domain name registration or resolution. IPAM can also provide monitoring, auditing, reporting, and security features for DNS and DHCP resources. Reference: [CompTIA Cloud+ Certification Exam Objectives], Domain 3.0 Maintenance, Objective 3.4 Given a scenario, implement automation and orchestration to optimize cloud operations.