Detailed Instructions: 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.
Problem:Context: The Nestin-class minesweeper is a class of minesweeper built specifically for naval mine clearing duties on rivers. The class was built for the needs of the Yugoslav Navy on the Danube river and was also sold to Hungary and Iraq during the 1970s and '80s.
Question: The document can be classified to which topic?
Options: 1)NaturalPlace, 2)Animal, 3)Building, 4)OfficeHolder, 5)MeanOfTransportation
Solution:
5