The correct answer is 38.
An amendment to the Constitution is a correction or an improvement to the original version of the document. The procedures of amending are stated in Article 5. So far, 27 Amendments have been approved.
To become part of the Constitution, an Amendment must be ratified after two-thirds of the House and Senate approve it, and it is then sent to the states for a vote.
Three-fourths of the states must affirm the proposed Amendment, which means 38 states of the present 50.
The other method of passing an Amendment is by Constitutional Convention, the Amendments must again be approved by three-fourths of the states.