What is the common name for the Big Island of Hawaii?

The correct choice identifies the Big Island of Hawaii by its common name, which is "Hawai'i." This can be attributed to the island's historical and cultural significance, as it was named after the first Polynesians who arrived on the island. The name "Hawai'i" not only represents the island itself but also the entire state of Hawaii.

The other islands given in the options—O'ahu, Kaua'i, and Maui—are separate islands within the Hawaiian archipelago. Each has its unique attributes and attractions, but they are not synonymous with the Big Island. O'ahu is known for its vibrant city life and historical sites, Kaua'i is dubbed the “Garden Isle” due to its lush greenery, and Maui is famous for its beautiful beaches and resorts. Hence, only "Hawai'i" correctly describes the Big Island, making it the right answer.