The chairman of the Public Accounts Committee in the Indian Parliament is the Leader of the Opposition Party. The Public Accounts Committee is a crucial parliamentary committee in India that is responsible for examining the audit reports of the Comptroller and Auditor General of India. It plays a vital role in ensuring financial accountability and transparency in government spending.

Option 2, the Speaker of Lok Sabha, is not the correct answer. The Speaker of Lok Sabha is the presiding officer of the Lower House of Parliament and is responsible for maintaining order and conducting the proceedings.

Option 3, the Deputy Speaker of Lok Sabha, is also not the correct answer. The Deputy Speaker assists the Speaker and performs their duties in their absence.

Option 4, the Chairman of Rajya Sabha, is also not the correct answer. The Chairman of Rajya Sabha presides over the proceedings of the Upper House of Parliament.

Therefore, the correct answer is option 1, the Leader of the Opposition Party.