Final answer:
Option 2 is answer. Virtualization is the characteristic that allows organizations to share processing resources in cloud computing, enabling efficient resource utilization.
Step-by-step explanation:
The characteristic that allows organizations to share the processing resources of many geographically dispersed computers across a network in cloud computing is virtualization. Virtualization enables multiple virtual machines to run on a single physical machine, thus allowing for the efficient sharing of processing resources among different organizations or users.
Virtualization abstracts the underlying hardware, creating a virtual environment that can be easily scaled and managed. This feature is crucial in achieving the scalability and flexibility offered by cloud computing, as it allows for dynamic allocation of resources based on demand.
For example, a cloud service provider can use virtualization to partition a physical server into multiple virtual machines, each running different applications for different organizations. These virtual machines can be dynamically allocated resources and can be geographically dispersed across the network, enabling efficient resource utilization.