Answer:
3
Step-by-step explanation:
On Topographic maps, the steepness of a slope is shown by lines evenly spaced yet very close together, on very steep slopes, it can even look like a thick outline darker than the surrounding areas.
Usually if you want to compare steepness, you just need to subtract the lowest elevation from the highest and divide that by the horizontal distance (from the scale of the map).
From what I can see in number 3, you have several lines evenly spaced close to each other, it looks that there is a cliff there.