Two important reasons to upgrade and patch are "Support Compliance" (A), ensuring the database
remains under Oracle’s support policy with access to updates, and "Security" (C), applying patches to
mitigate vulnerabilities and protect data. "Validation of application" (B) is a byproduct, not a primary
reason, and "Restructure the database" (D) is unrelated to patching. Oracle’s maintenance guides
emphasize compliance and security as key drivers.
Reference: Oracle Patching Best Practices, OCI Security Maintenance Guide.
