Very few cameras record 24 bit audio so you can safely use 48/16 on your Zoom recorder.
To be 100% sure though, load any camera footage info Vegas, switch the view setting in your Project Media tab to Detailed and scroll over to the Bit Depth column.

p.s. some folks on here don’t like going to different sites to view an image, especially when you can upload here using the image upload tools that Creative Cow gives you.