Final answer:
AES-256 encryption is a data security feature found in fields that require high levels of data protection, using a 256-bit key to safeguard sensitive information.
Step-by-step explanation:
A requirement to use AES-256 encryption would normally be found in a document or policy related to data security or information technology. This particular encryption standard is an advanced version of the Advanced Encryption Standard (AES) and offers a high level of security by using a 256-bit key to encrypt data. It is widely recognized and used in various forms of technology to protect sensitive and confidential information from unauthorized access. AES-256 is considered one of the most robust encryption methods available, meeting security requirements for industries such as finance, healthcare, government, and others that handle high-value or sensitive data.