Final answer:
An affiant is a person who makes a sworn written statement, typically in the context of legal proceedings, such as both criminal and civil cases.
Step-by-step explanation:
An affiant is a person who makes a sworn statement in writing. This term is commonly used in the context of legal matters. When a person, known as the affiant, signs an affidavit, they are making a written statement that they swear is true, which is then verified by a notary public or other authorized officer. The statement must be made under oath or on penalty of perjury, indicating that the affiant is aware that they must be honest in their declaration.
Therefore, the correct answer to what an affiant is would be: A witness who has sworn a written statement. It is important to understand, however, that an affiant is not just limited to criminal cases; they can also provide a sworn statement in civil cases and other legal proceedings.