Which of the following amendments is part of the Bill of Rights?

The 1st Amendment is indeed part of the Bill of Rights, which comprises the first ten amendments to the United States Constitution. These amendments were ratified in 1791 and are designed to protect individual liberties and rights against governmental infringement. The 1st Amendment specifically guarantees fundamental freedoms such as the freedom of speech, freedom of religion, freedom of the press, the right to assemble peacefully, and the right to petition the government.

In contrast, the 12th, 18th, and 20th Amendments address other areas of governance and societal issues. The 12th Amendment redefines the presidential election process, the 18th Amendment established Prohibition, and the 20th Amendment tweaked the terms of office for federal officials. None of these amendments are included in the Bill of Rights, as they were enacted after the Bill of Rights was ratified, focusing instead on specific governance procedures and social reforms.