What does the Bluetooth icon in the menu bar signify when it’s visible?

The Bluetooth icon appearing in the menu bar indicates that Bluetooth is active and that the system is connected to at least one Bluetooth device. This visual cue confirms that the Bluetooth functionality is not only enabled, but also that there is a successful connection with compatible devices such as headphones, mice, keyboards, or other peripherals.

When the Bluetooth icon is shown, users can easily access additional Bluetooth settings or manage their connected devices directly from the menu bar. This provides a convenient way to monitor Bluetooth status and connectivity without needing to delve deeper into system preferences.

It's important to note that other options refer to various states of Bluetooth functionality that do not describe an active connection to devices, thereby making the correct answer clear in the context of the question.