Explanation:

- Option 1: President

- The President of India is the Supreme Commander of the Armed Forces, but is not directly responsible to Parliament for defence matters.

- Option 2: Prime Minister

- The Prime Minister is the leader of the government and plays a key role in major defence decisions but is not directly responsible for defence matters to Parliament.

- Option 3: Defence Minister

- Correct Answer: The Defence Minister is directly responsible to Parliament for all matters concerning the Defence Services.

- Option 4: Cabinet Committee on Political Affairs

- This committee includes the Prime Minister and senior ministers, and deals with major political and defense decisions, but it is the Defence Minister who is directly responsible to Parliament.