The answer is number 3 because it steadily increases or goes up so it's a straight line it doesn't go down or it doesn't decrease the number of guests!
In 2001 the museum started off with a high amount of visitors.In 2002 there began to be a decrease until 2005 where a slight increase happened,then in 2006 there were more of an increase in visitors being higher than the amount in 2001.
