Medieval european cities usually grew
a. along trade routes
b. in remote mountain areas
c. near important universities
d. away from rivers or sea coasts

it affected it because the kingdoms (with trade) slowly got richer and richer.

map scale refers to the relationship (or ratio) between distance on a map and the corresponding distance on the ground. for example, on a 1: 100000 scale map, 1cm on the map equals 1km on the ground.