Species whose populations follow a boom-and-bust curve are most affected by
reproductive factors
health factors
density-dependent factors
density-independent factors

Density independent factors is your answer ! approved by me getting it right on the test .

A) early horses is your answer

Are you asking about a street map usage  if so here is your answer  a street map for a very limited area could simply be a bit map or a .jpg image.  but a more general map would probably store the streets as vectors.  but you shouldn't assume that there is one way to do it