Final answer:
A private cloud is a dedicated computing environment for a single organization, with isolated resources not shared with the public. Option 1 best defines a private cloud as a collection of resources not shared with the general public, which may include both on-premises and off-premises deployments specifically for one organization.
Step-by-step explanation:
A private cloud is defined as a cloud computing environment where computing resources are isolated and intended for use by a single organization, or a specific subset of users from that organization. It's a dedicated infrastructure that provides computing resources such as servers, storage, and networking capabilities.
Looking at the provided options, a private cloud is most accurately defined by Option 1: A collection of resources that are not shared with the general public. This option describes how the resources are dedicated to a single organization rather than being available to the public, which is a defining characteristic of a private cloud.
Option 4 could also be partially correct when mentioning resources that are 'isolated on-premises for use by an organization,' however, it suggests only an on-premises deployment model, which is not the only way to deploy a private cloud. A private cloud can also be hosted off-premises by third-party providers but still maintained exclusively for one organization. Therefore, Option 1 is the most accurate definition of a private cloud as it includes both on-premises and off-premises scenarios.