A newly acquired subsidiary uses a separate identity provider with no federation to the parent company. Executives want immediate single sign-on access to the subsidiary's financial reporting system. The subsidiary's IT team warns their directory contains orphaned accounts from prior layoffs. What should you address FIRST?
A. Establish federated trust between both identity providers
B. Perform an access review and remove orphaned accounts in the subsidiary's directory
C. Provision executive accounts directly in the subsidiary's identity provider
D. Implement multi-factor authentication on the financial reporting system