Covalent bonds formed differently than ionic bonds. How is the difference observed in the properties of covalent substances

If you get a map and put the countries a states all together it forms all one piece you can also tell because of the earth quakes

1) the mayans built pyramids just like the egyptians. the mayans also used hieroglyphics like them.2) power was passed down by family. for example, if the father dies, the son would be the next king.3)they both built pyramids for their structures.4)the main crop for the mayans was maize.5)they also grew manioc, beans,  squash,  amaranth, and chile peppers.

According to edgenuity, the answer is c.