Ageographer who studies the similarities between two places most often uses which of the six elements

A hundred years ago, in the early months of 1916, America stood possessed of a magnificent, visionary, slightly confused and inchoate idea: national parks. These would be parks for the American citizenry, not pleasure grounds or private hunting reserves for nawabs and kings; parks to be shared, even, with visitors from around the world.

At that point 14 national parks already existed in the United States, the oldest being Yellowstone, which had been set aside by federal law, back in 1872, as the first national park anywhere in the world. The other U.S. parks, representing a diverse sample of majestic landscapes, all west of the Mississippi, included Yosemite in California (originally a state park, nationalized in 1890), Wind Cave in South Dakota (1903), Glacier in Montana (1910), and Rocky Mountain in Colorado (1915). There were also 21 national monuments—a form of protection more easily achieved because it could come by presidential decree under the Antiquities Act (passed in 1906), as robustly exploited by Theodore Roosevelt during his last three years as president. That early list of national monuments included Devils Tower, Chaco Canyon, Muir Woods, and the Grand Canyon.

What they said. Sorry i need points :)

the answer to this question is d