In a business-to-business (B2B) collaboration scenario, Azure facilitates secure access for external partners by allowing them to use their own credentials, typically through Single Sign-On (SSO) and Multi-Factor Authentication (MFA). Considering the need for cost-effectiveness, compliance with industry standards, and scalability, which of the following options best describes the authentication methods Azure typically uses to ensure the security of shared resources in such scenarios? (Choose two options from A, B, C, D)