Which virtualization solution allows for isolated execution environments for applications, as seen in Docker and Open VZ?

The correct choice identifies containerization as the virtualization solution that provides isolated execution environments for applications. Docker and Open VZ are prime examples of containerization technologies.

Containerization enables applications to run in lightweight and isolated environments, called containers, which share the same operating system kernel but run independently from one another. This allows for efficient resource use, faster deployment, and simplified scaling because containers can be started and stopped quickly without the overhead of a full virtual machine.

In contrast, Type 1 hypervisors create and run full virtual machines that include an entire operating system with its own kernel, which is a heavier solution compared to containerization. Terminal Services refer to remote access technologies that enable users to run applications on a remote server and is not focused on isolation like containerization. Application virtualization allows applications to run on a host operating system without directly installing them on the OS but doesn't specifically refer to the lightweight, isolated environments typical of container technology. This understanding clarifies why containerization is the relevant answer in this context, emphasizing its role in creating isolated application environments.