Embedded cryptoprocessor (option B): An embedded cryptoprocessor is a specialized chip that is designed to perform cryptographic operations, such as encrypting and decrypting data, generating and verifying digital signatures, and generating and storing cryptographic keys. By installing an HSM with an embedded cryptoprocessor in the mobile device, the organization can ensure that sensitive data is processed and stored in a secure manner.
Hardware-backed public key storage (option C): A hardware-backed keystore is a secure storage area that is physically isolated from the rest of the device and is designed to store cryptographic keys. By using an HSM with hardware-backed public key storage, the organization can ensure that public keys are stored in a secure and tamper-resistant manner, which is important for ensuring the security of digital certificates and other sensitive data.

An active-active cluster does nothing if the cloud provider goes down. One of the main features of multi-cloud is redundancy. https://www.cloudflare.com/learning/cloud/what-is-multicloud/