Which statement is true regarding the necessity of internet access for the 3CX server?

The statement that internet access is not needed if no external communications are involved is true. In scenarios where a 3CX server is utilized solely for internal communications within a local network, such as between internal extensions, there is no requirement for internet connectivity. All internal calls can be made without needing access to the internet since the system operates perfectly in a local environment.

However, it's important to recognize that features such as VoIP services, management functions, and remote access to the system would necessitate an internet connection. Thus, while the server can function effectively in a purely local setup, any desire to leverage external communication capabilities, cloud-based management, or integration features would require internet access.