Which characteristics pertain to "the cloud"?

The characteristic that pertains to "the cloud" is that it is accessed over a network. This reflects the fundamental nature of cloud computing, where resources and services are provided over the internet. Users connect to cloud services through various devices without needing to be physically present at a specific location. This accessibility allows for flexibility, enabling users to access their data and applications from anywhere, as long as there is a network connection.

The other options do not accurately describe the cloud. Requiring physical servers is a characteristic of traditional on-premises infrastructures rather than cloud solutions, which often rely on virtualized environments and can utilize shared resources. Fixed storage capacities contradict the cloud model, which typically offers scalable storage solutions, allowing users to adjust their storage needs dynamically. Lastly, the cloud supports multiple users simultaneously, making collaboration possible, which is contrary to the idea of single-user access only.