C. To address data integrity, it is common to use encryption in combination with message authentication codes (MAC) or hash functions. In this case, encrypting the data using the AES algorithm before transmission and incorporating a mechanism for verifying the integrity of the data (such as using a HMAC - Hash-based Message Authentication Code) would help detect if the data was tampered with during transmission.
Options A, B, and D do not specifically address the need for integrity checking during transmission:
A. Implement IPsec in addition to SSL/TLS: IPsec is used for network layer security and could be redundant when SSL/TLS is already in place.
B. Switch to using SSH for data transmission: While SSH provides encryption and integrity checking, it may not be the best choice for application-level data transmission, especially in a cloud environment.
D. Use the cloud service provider's built-in encryption services: it may not be sufficient for ensuring integrity during data transmission unless combined with an appropriate integrity verification mechanism.