The Graph Shows the Monthly Revenue in Millions of Dollars

Multiple Choice

The graph shows the monthly revenue in millions of dollars of a growing company after the company doubled its advertising. Use the graph to solve the problem.
-During what period of time is the company's monthly revenue decreasing?

A) From the time that the advertising was doubled until the 9th month
B) From the time that the advertising was doubled until the 6th month
C) From the 9th month to the 12th month
D) From the 6th month to the 9th month