Which Clean Core Approach principle promotes the isolation of cutom code from standard SAP functionality?

The Clean Core Approach emphasizes keeping the SAP digital core free from modifications and isolating custom code:

Separation of Concerns → Custom logic/extensions are isolated from SAP standard functionality, ensuring upgrades and innovations are not disrupted.

Other principles (modular design, coding standards, reusability) are good practices but not specifically tied to Clean Core’s goal of isolating custom code.

Thus, the correct principle is Maintain separation of concerns.