I want to know the answer to the following question:
What is Iran's most popular online social network?
All the background I'm provided with is that "Direct access to Facebook has been blocked in Iran since the 2009 Iranian presidential election protests, due to organization of the opposition movements on the website; but however, Facebook has around 12 to 17 million users in Iran who are using virtual private networks and proxy servers to access the website.". Is that enough to answer the question?