Hint: Whales and dolphins are not the fishes but they belong to the kingdom mammals. Their bodies look like fish but perform the function like mammals, they give birth like mammals, and they provide their children their milk and many things like mammals. Dolphins are observed to be very social as they hunt and play together.
Chilika Lake is a brackish water lagoon, that is located in Odisha state on the east coast of India, at the mouth of the Daya River, flowing into the Bay of Bengal. It is the largest coastal lagoon in lIndia and also is the second largest brackish water lagoon in the world. it is the largest wintering ground for migratory birds that is present on the Indian subcontinent.
Now let us find solution from given options:
A.Ganges dolphin : it is a south Asian river dolphin. It is an endangered species. It is divided into subspecies that is Ganges river dolphin and Indus river dolphin.
B.Irrawaddy dolphin : it is a kind of Euryhaline dolphin that is present in south Asia. It is present in Bay of Bengal and also in Chilika lake.
C.Narwhal : it is also called as Narwhale and is medium in size. It has a tooth. It is located in Canada and Russia.
D.Porpoise : they are aquatic marine mammals that are similar to dolphins. These are actually whales.
Hence, the correct answer is option (B)
Note: Dolphins and whales do not breathe in water with the help of their gills. As it is clear by the fact that dolphins and whales belong to mammals, they breathe normally in the air, like normal mammals do, like take an example of humans only, so dolphins and whales have to come at the top of the water, where they can take oxygen for breathing