The company ABC recently contracted a new accountant. The accountant will be working with the financial statements. Those financial statements need to be approved by the CFO and then they will be sent

A cryptographic hash algorithm generates a deterministic fingerprint of the document at the moment the CFO approves it; the CFO can share this hash value through a separate channel. When the accountant receives the document, they recalculate the hash and compare it to the original - if the values match, the document is unmodified. This directly addresses integrity, one of the CIA triad pillars, and is the standard cryptographic mechanism for detecting unauthorized or accidental changes to data.

An Excel password controls access to the file but does not provide a cryptographic mechanism to detect whether an authorized or unauthorized party modified the document's content after approval.

Sending the document through two channels adds redundancy and helps detect transmission errors but does not cryptographically prove the content was not intentionally altered on either delivery path.

Using a dedicated USB drive addresses physical transport security but does not prevent or detect modification of the document's content before or after it is placed on the drive.