The correct answer is option 2, Tropical monsoon forest.

Sal trees are indeed the typical species of tropical monsoon forests. These forests are characterized by a distinct monsoon climate, with a wet season and a dry season. They are found in regions that experience a seasonal change in precipitation, such as India, Southeast Asia, and parts of Africa.

The monsoon forests are known for their dense vegetation and abundant rainfall during the wet season. Sal trees, scientifically known as Shorea robusta, are one of the dominant tree species in these forests. They are tall and have broad, evergreen leaves that provide shade and protection to other smaller plants and animals.

The other options mentioned in the question are not the correct habitats for Sal trees. Tropical rainforests (option 1) have a different climate and tree composition, with a higher diversity of tree species. Taiga forests (option 3) are located in the subarctic regions and consist mainly of coniferous trees. Tundra forests (option 4) are cold, treeless landscapes found in polar regions.

Therefore, the correct answer is option 2, Tropical monsoon forest.