A company has extended Business Central.

 B. Include extension translation files with the submission.

AppSource submissions require that the extension be localized to different languages, and including translation files is part of the requirement.

 C. Ensure the app file is digitally signed.

Digitally signing the app file is a security requirement for AppSource submissions to ensure the integrity and authenticity of the app.

 E. Use data classification on all tables and extension fields.

Microsoft requires that all data, especially personal data, be classified using the data classification feature to comply with GDPR and other data privacy regulations.