14bit file from the Camera. But I see only 8bit and 16bit processing options in capture one.

Hi I am currently Nikon d850 user. I believe d850 can create 14bit max file. 

However, when I want to process raw files via Capture one, it shows only 8bit or 16bit processing options in capture one. 

what happen when I process 16bit option in Capture one with 14bit raw file from Nikon( or any other camera create only 14bit max) ? 

is it real 16bit? or they just showing 16 bit file? confusing