The correct answer is option 'B' - Flying Squirrel.

Explanation:
The Red Data Book is a comprehensive record of the conservation status of various species of plants and animals found in a particular country. In India, the Red Data Book is maintained by the Zoological Survey of India (ZSI). It categorizes species into different categories based on their population status and threat level.

Flying squirrels are not listed in the Red Data Book in India. Here's an explanation of why:

1. The Red Data Book:
The Red Data Book is an important tool for the conservation of biodiversity. It identifies species that are at risk of extinction and helps in formulating conservation strategies. The book categorizes species into different categories based on their population status, distribution, and threat level. The categories include Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, and Least Concern.

2. Importance of the Red Data Book:
The Red Data Book helps in identifying species that require immediate conservation action. It raises awareness about the declining population of certain species and the need to protect their habitats. The book also helps in prioritizing conservation efforts and allocating resources accordingly.

3. Black Bunch, Tiger, and Leopard:
Black Bunch, Tiger, and Leopard are all listed in the Red Data Book in India. These species are facing various threats to their survival, including habitat loss, poaching, and illegal trade. The Red Data Book categorizes these species as either Endangered or Vulnerable, highlighting the urgent need for their conservation.

4. Flying Squirrel:
Flying squirrels, on the other hand, are not listed in the Red Data Book in India. This suggests that their population status and threat level are not currently of concern. Flying squirrels are a group of arboreal squirrels capable of gliding through the air using a specialized membrane called a patagium. While they may face localized threats or habitat loss in certain regions, their overall population is not considered at risk in India.

In conclusion, among the given options, the wild animal that is not listed in the Red Data Book in India is the Flying Squirrel. This indicates that its population status and threat level are not currently a cause for concern.