Explanation:

- Scrutiny: Examining documents or accounts carefully to correct errors or discover information. Often done internally without formal qualification requirements.

- Investigation: A detailed probe aimed at uncovering facts, irregularities, or fraud. This may not adhere to the structured approach of an audit.

- Audit: A systematic examination of financial records by an independent and qualified individual. This process ensures accounts are accurate, compliant, and free from material misstatement.

- Inspection: A general review or assessment of certain records, assets, or processes, less comprehensive than an audit.