Why may a cloud-stored file be unavailable without internet access?

Correct answer: Online access depends on the network

The governing concept is the difference between remote storage and local storage. A cloud-stored file is accessed through a service over a network, so the device generally needs internet connectivity and valid service access to retrieve or synchronise it. Without the network, the online copy may be unavailable, although a previously downloaded offline copy could still work. The other options do not explain network dependence.