Desktop Wallpaper Over Spanned Monitor

I've downloaded and installed some beautiful themes from Windows Store with some very nice wallpapers. My primary display has a resolution of 5760x1080, three 23" monitors brought together using Nvidia's Surround Feature.

The wallpapers span across the three monitors but the images are grossly enlarged and do not show fully on the display. Most of the pictures are cropped.

Is there a way, a setting perhaps, that will allow me to adjust the wallpaper to a size that I can enjoy the full poicture?

Is the wallpaper of the same dimension, 5760x1080?

Right-click on desktop, select Personalize, and try out each of the settings under Background -> Choose a fit.

One of these may resolve the problem.