Which of the following statements are true with respect to the Red Data Book by International Union for Conservation of Nature (IUCN)?
A. Dinosaur and Rhynia are extinct species that are not surviving today.
B. Leopard and alligator are inadequately known species that exist on earth but not much is known about them.
C. Rhinoceros, lion and godawan also come under extinct species.
D. Giant panda and snow leopard are rare species that are very uncommon, scarce and can become endangered in near future.
Choose the correct answer from the options given below: