Correct Option
As per Article 368 of the Constitution of India, an amendment to the Constitution can be initiated only by the introduction of a Bill for the purpose in either House of Parliament, that is, the Lok Sabha or the Rajya Sabha. Both Houses possess co-equal power in this regard.
Incorrect Options
The State Legislatures do not have the power to initiate a constitutional amendment. Their role is limited to ratification for certain types of amendments after the Bill has been passed by Parliament, as specified in Article 368(2).
The President of India does not have the power to initiate a constitutional amendment. A Bill for constitutional amendment does not require the prior recommendation of the President for its introduction in Parliament.