Which of the following is a common type of document that requires notarization?

Powers of attorney are a common type of document that requires notarization because they grant one individual the authority to act on behalf of another in legal or financial matters. Notarization in this context serves several important purposes: it verifies the identities of the parties involved, ensures that the principal is signing the document willingly and without coercion, and provides a legal safeguard that helps prevent fraud.

When it comes to legal documents such as powers of attorney, the presence of a notary adds a level of trustworthiness and formality. Notaries are trained to ensure that all necessary procedures are followed, which is especially crucial in matters that involve significant legal rights and obligations.

In contrast, emails do not typically require notarization because they serve as informal communication rather than legal instruments. Birth certificates are vital records that are usually issued by government authorities, thus do not require a notary to validate their authenticity. Business cards, while they may contain important information about a person's professional identity, do not have the legal implications that necessitate notarization.