Which statement defines an "affidavit"?

An affidavit is specifically defined as a written declaration made under oath. This means that the individual who creates an affidavit swears that the information contained within it is true and accurate to the best of their knowledge. Affidavits are often used in legal contexts to provide testimony or evidence without the individual needing to appear in court. The written format allows for clear documentation of statements and can be utilized in various legal proceedings to support claims or defenses.

The other options provided do not accurately capture the unique nature of an affidavit. A type of legal contract involves contractual agreements between parties and is not specifically about sworn declarations. A legal brief outlining evidence is a detailed document prepared to argue a case in court and is different in purpose and function from an affidavit. A sworn oral statement made in court refers to the testimony given during a trial, which is distinct from the written nature of an affidavit. Therefore, the best definition of an affidavit is indeed a written declaration under oath.