Definition: In this task, you are given a text which is the body of a document. You are given a question and options. Pick the correct number. Don't generate anything else apart from the numbers provided in options.
Input: Context: The Round Barn Pilot Grove Township is an historical structure located in rural Montgomery County Iowa United States. It was built in 1912 and has been listed on the National Register of Historic Places since 1986. The building is a true round barn that measures 60 feet (18.3 m) around. It is covered in white vertical siding and features a two-pitch roof a small dormer on the south side and an 18 foot (5.5 m) central silo.
Question: The document can be classified to which topic?
Options: 1)Building, 2)NaturalPlace, 3)OfficeHolder, 4)Plant
Output:
1