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.

Context: This page is about the pioneering biplane of 1910. For the World War I bomber see Caproni Ca.1 (1914).The Caproni Ca.1 was an experimental biplane built in Italy in 1910. It was the first aircraft to be designed and built by Gianni Caproni although he had previously collaborated with Henri Coanda on sailplane designs. The Ca.1 was an unorthodox design with an uncovered rectangular truss as a fuselage. Its two-bay wing cellule featured unstaggered mainplanes of equal span.
Question: The document can be classified to which topic?
Options: 1)Company, 2)NaturalPlace, 3)Building, 4)MeanOfTransportation
4