Consider the following statements regarding the Delimitation Commission and the process of delimitation in India:
1. The Delimitation Commission is appointed by the Prime Minister of India.
2. The last delimitation exercise that changed the state-wise composition of the Lok Sabha was completed in 1996.
3. The 87th Amendment Act of 2003 provided for the delimitation of constituencies on the basis of the 2001 census.
4. The Delimitation Commission's orders can be challenged in court.
How many of the statements given above are correct?