The Red Data Book contains data of :
The explanation for the correct option:
Option(B) Endangered / Threatened species.
The Red Data Book helps us in providing complete information for research, and studies and also for monitoring the programs on rare and endangered species and their habitats.
This book is mainly created to identify and protect those species which are on the verge of extinction.
Currently, the International Union for Conservation of Nature(IUCN) maintains the Red Data Book.