Rugged and undulating are the two ways which shows that topography effects the population of an area.
Explanation:
Topography has a great effects on the distribution of population. Rugged topography is a type of topography in which the surface is uneven and rocky while undulating topography refers to land which is just like waves having lower and higher points. So both of these topography decreases the population of people because on these lands walking is difficult due to no roads and uneven surface so that's why people settle on the plain areas.
