Explanation:

Let's analyze the options:

• Den: A den is a home or shelter for certain animals, like a lion or bear.
• Roof: A roof is part of a building, not necessarily associated with animal homes.
• Burrow: A burrow is a home or shelter typically used by small animals like rabbits or rodents.
• Nest: A nest is a home for birds or other animals.

The odd one out is Roof because it refers to a part of a human-made structure, while the others (Den, Burrow, Nest) are natural shelters used by animals.

So, the correct answer is: (B) Roof.