Answer:
D. American bison
Step-by-step explanation:
Grizzly bear, gray wolf, passenger pigeon, Carolina parakeet, ivory-billed woodpecker, elk, and American bison are the wildlife species which have been lost in Oklahoma in the first half of the twentieth century. Elk and American Bison are the two species that have been reintroduced in Oklahoma. Several measures have been taken by the government to help in the protection of the endangered species. The implementation of the acts helps in the preservation, protection, and increase in the number of endangered species.