Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to pair a cell phone to a bluetooth headset [title] Charge your headset. [step] Starting with a full charge on both devices ensures that process won't be interrupted by a low battery. [title] Put your headset in " pairing mode.

Ending1: [step] " this mode is app-specific that will hold up the phone wirelessly. [title] Connect your headset to your mobile's bluetooth. Ending2: [step] " a low battery puts your headset in " pairing mode. " by pairing you can safely switch between both devices. Ending3: [step] " this mode allows your headset to be charged on both devices while simultaneously neutralizing the data held by the headset. This mode takes around 6 hours, and you must be listening and maintaining online communication to use the device. Ending4: [step] " the process is similar across all bluetooth headsets, but there might be slight variations depending on model and manufacturer. [substeps] For almost all headsets, this is done by starting with the headset power off, then pressing and holding the multi-function button (the button you press to answer a call) for a few seconds.

Answer format: ending1/ending2/ending3/ending4