Read this: Brigham Young University's origin can be traced back to 1862 when a man named Warren Dusenberry started a Provo school in a prominent adobe building called Cluff Hall, which was located in the northeast corner of 200 East and 200 North. On October 16, 1875, Brigham Young, then president of the LDS Church, personally purchased the Lewis Building after previously hinting that a school would be built in Draper, Utah in 1867. Hence, October 16, 1875 is commonly held as BYU's founding date. Said Young about his vision: "I hope to see an Academy established in Provo... at which the children of the Latter-day Saints can receive a good education unmixed with the pernicious atheistic influences that are found in so many of the higher schools of the country."

What year can BYU's origin be traced to with a building called Cluff Hall?
What is the answer? (If it cannot be answered, return "unanswerable")
1862