What is necessary for a Bill to become law after being passed?

For a Bill to become law after it has been passed by the legislature, it is necessary for it to receive the assent of the President. This is a crucial step in the legislative process in many political systems, particularly in parliamentary systems like India's. After both houses of the legislature have approved the Bill, it is sent to the President for approval. If the President grants assent, the Bill is enacted as law. If the President withholds assent or returns the Bill for reconsideration, further action may be required by the legislature to ultimately pass the Bill into law.

The other options do not reflect the legislative process accurately in most contexts. A majority vote is essential for the passage of the Bill within the legislative arena but does not complete the legislative process. Approval by the Chief Justice or a public referendum is not a required step for a Bill to become law, and thus they do not play a role in the standard legislative procedure following the Bill's passage.