Which of the following API types does SAP recommend to use to achieve clean core...

Clean Core Integrations:

Clean core principles emphasize keeping customizations outside the SAP core to simplify upgrades and maintenance.

APIs are the recommended mechanism for integration to preserve the core system.

Recommended API Types:

OData (A):RESTful APIs designed for modern web-based integrations.

SOAP (D):Protocol-based API suitable for enterprise-grade integrations.

Why Other Options Are Incorrect:

IDoc (B):Legacy data exchange format, not suitable for clean core.

RFC (C):Requires tight coupling, which contradicts clean core principles.

References:

SAP API Guidelines: Clean Core Recommendations.