Solution

In cloud security, protecting data in multi-tenant environments is a major challenge. Multi-tenant environments involve sharing physical resources among multiple users or organizations, which can lead to data breaches if proper isolation and security measures are not implemented. Ensuring that data is secure and isolated from other tenants is critical to maintaining privacy and compliance with regulations. Why Other Options are Wrong: a) Scalability of machine learning algorithms is a challenge in AI/ML but not directly related to cloud security. b) Managing data storage in relational databases is a database management issue rather than a cloud security challenge. d) Optimizing sorting algorithms is related to algorithm design and performance, not cloud security. e) Implementing neural network architectures is a concern in AI/ML and not specific to cloud security.