Neelgai belongs to the following family:

Cow
Goat
Sheep
Deer

The correct answer is (d), deer.

Neelgai is a large, wild antelope found in India and Pakistan. It is the largest member of the deer family, Cervidae. Neelgai are herbivores and their diet consists mainly of grasses, leaves, and fruits. They are social animals and live in herds of up to 100 individuals.

Cows, goats, and sheep are all members of the Bovidae family. They are all ruminants, which means that they have a four-chambered stomach that helps them to digest their food. Cows are the most common type of domesticated animal in the world. They are used for their milk, meat, and leather. Goats are also domesticated animals and are used for their milk, meat, and wool. Sheep are also domesticated animals and are used for their wool and meat.

Deer are members of the Cervidae family. They are all hoofed animals with branched antlers that they shed and regrow each year. Deer are found in forests, grasslands, and mountains all over the world. There are over 50 different species of deer, including white-tailed deer, red deer, and elk.