When Mental Maps Are Described as Being Partially Hierarchical, What

When mental maps are described as being partially hierarchical, what is meant?

A) They are hierarchically arranged only at the level of details.
B) They are hierarchically arranged in terms of regions, but not at the level of details.
C) Euclidean rules of hierarchies are only partially applied.
D) Estimating distances involves a re-perceptual process.