What is one of the identifying features of the Norway Rat?

The Norway Rat is characterized by several distinct features, one of which is having a tail that is typically much shorter than its body, rather than longer. Therefore, the idea that they may often have a dark-colored tail is more accurate when considered in the context of their overall appearance and common coloration traits.

Norway Rats usually have a robust body shape, a blunt snout, and small ears which contribute to their identification. The coloration of their fur often ranges from brown to gray, and their tails are usually a lighter shade compared to the rest of their body, sometimes appearing darker as they age. This combination of features, particularly the coloration, assists pest control professionals in identifying these rodents in various environments, such as urban and suburban settings.

The other features mentioned in the options do not accurately fit the Norway Rat species—such as being the smallest rat species, which is incorrect as they are among the larger rats; having a tail longer than their body, which is characteristic of other rat species; and never burrowing or gnawing, which contradicts their well-known behavior as persistent gnawers and burrowers.