Statement 1 is correct as a National Emergency can be proclaimed by the President when the security of India or any part thereof is threatened by war, external aggression, or armed rebellion. Statement 2 is also correct because, during a National Emergency, the central government acquires the power to give directions to states on any matter. Statement 3 is incorrect as the state legislature can be dissolved or suspended during a National Emergency. Statement 4 is correct in that the Proclamation of Emergency can continue for a maximum period of six months at a time, but it must be approved by resolutions of both Houses of Parliament. Therefore, the correct option is 2: 1 and 2 only.