An area of land planted with fruit trees is called orchard.

Orchards are the areas specifically dedicated to fruit trees. It can be naturally occurring open area or enclosed farm land. The fruit trees include apples, oranges, bananas, and cherries.

Other options are incorrect for the following reasons:
- Forest is a large area covered with trees, regardless of the type.
- Top hill is the hilly or mountainous region having different types of trees suitable for the climate.
- Fauna refers to all the animals of a particular region.

Hence. option B is correct.