Which rat prefers fruits, vegetables, nuts, and grains?

The correct choice is the roof rat, which is particularly known for its preference for fruits, vegetables, nuts, and grains. Roof rats, or Rattus rattus, are primarily found in urban and coastal areas and often inhabit trees, attics, and other high places. Their diet is heavily influenced by their natural habitat, where they tend to forage for food sources that are higher off the ground. This makes them more inclined to consume foods that are abundant in gardens and orchards, particularly fruits and vegetables.

In contrast, other rodents such as the Norway rat typically favor a diet that includes more protein and is less focused on fruits and vegetables, often leaning towards scavenging for meats and other waste products. The house mouse also has a diverse diet but is less inclined to eat larger amounts of fruits and vegetables compared to roof rats, focusing more on grains. The mention of black flies in this context does not pertain to the question, as they are not rodents and have a completely different dietary habit, being insects that feed mainly on nectar and other plant-based substances. Understanding these dietary preferences helps in implementing effective pest control strategies and understanding rodent behavior in urban settings.