Definition: In this task, you are given a text which is the body of a document. Your job is to classify the topic of the document into these categories: 1)Company, 2)Educational Institution, 3)Artist, 4)Athlete, 5)Office Holder, 6)Mean of transportation, 7)Building, 8)Natural place, 9)Village, 10)Animal, 11)Plant, 12)Album, 13)Film, 14)Written work. Your output should be the category number. Don't generate anything apart from numbers 1-14.
Input: Text:  The Northrop Grumman X-47C is designed to be a stealth unmanned aircraft. Its ancestors the X-47A and the X-47B made this unmanned aircraft possible to carry out the stealth that was needed in order to be undetectable by radar. It is planned to have a payload of 10000 pounds (4500 kg) significantly exceeding that of the X-47A.

6