Extract the answer to the question from the following context. Question: Which of the following was not built during the WPA era: the Rose Garden, Oklahoma City or the Butterfly Garden? Context: Oklahoma City has a major park in each quadrant of the city, going back to the first parks masterplan. Will Rogers Park, Lincoln Park, Trosper Park, and Woodson Park were once connected by the Grand Boulevard loop, some sections of which no longer exist. Martin Park Nature Center is a natural habitat in far northwest Oklahoma City. Will Rogers Park is home to the Lycan Conservatory, the Rose Garden, and Butterfly Garden, all built in the WPA era. Oklahoma City is home to the American Banjo Museum, which houses a large collection of highly decorated banjos from the early 20th century and exhibits on the history of the banjo and its place in American history. Concerts and lectures are also held there.
Oklahoma City