Raster pixel question

Hi all,

I have used model builder to calculate a site suitability raster using the weighted overlay tool.

I now have a site suitability raster and I have to pick one of four polygons that overlay the raster as the most suitable.

I'm wondering is there any tool I can use the calculate which one of the areas has the most number of pixels in a certain category? or if there is any Arc tool that will pick an area with a high concentration of pixels of a particular value?

I have attached an image of my site suitability raster and the four polygons; I have to rank these from one to four in order of their suitability.

Thank you in advance!

Dónal