The correct answer is (b), Western Ghats.
The Western Ghats are a mountain range in the western part of India. They are a biodiversity hotspot, meaning they are home to a large number of plant and animal species that are found nowhere else in the world. The Western Ghats are also a UNESCO World Heritage Site.
The Eastern Ghats are a mountain range in the eastern part of India. They are not as biodiverse as the Western Ghats, but they are still home to a number of unique plant and animal species.
The Thar Desert is a desert in the northwestern part of India. It is not a biodiversity hotspot, but it is home to a number of desert-adapted plants and animals.
The Bay of Bengal is a bay in the Indian Ocean. It is not a biodiversity hotspot, but it is home to a number of marine plants and animals.
The Western Ghats are a biodiversity saturated area in India because they are home to a large number of plant and animal species that are found nowhere else in the world. The Western Ghats are also a UNESCO World Heritage Site.