Answer:
The bonds must be non-polar.
Step-by-step explanation:
The water molecules are polar, so they wouldn't be attracted to the surface. This means the water would bead up and curve away from the surface it landed on.
When water beads up, this happens because the water molecules are more strongly attracted to each other by the polar bonds than they are to the surface by non-polar interactions.
To summarize:
On a nonpolar layer, water beads up because the attraction to each other is stronger than the surface.
Hope this explained it well.