Consider the following statements about the Chief of Defence Staff (CDS) as Head of the Department of Military Affairs:

1. The CDS exercises direct military command over the three Service Chiefs.

2. The CDS acts as the permanent Chairman of the Chiefs of Staff Committee (COSC).

3. The CDS functions as the Principal Military Adviser to the Raksha Mantri on tri-Service matters.

Which of the statements given above is/are correct?