noun
identity document; identification document
Official document used to verify a person's identity, such as a driver's license, passport, or My Number card. Common in administrative and financial contexts.
口座を開設するには本人確認書類が必要です。
You need an identity document to open an account.
本人確認書類として運転免許証を提示してください。
Please present your driver's license as identification.
身分証明書 is a more general term for any ID card, while 本人確認書類 specifically refers to documents used for identity verification in official procedures.
Compound of 本人 (the person in question), 確認 (confirmation), and 書類 (documents).