A. Delete the access keys for the account root user in every account.
B. Create an admin IAM user with administrative privileges and delete the account root user in every account.
C. Implement a strong password to help protect account-level access to the AWS Management Console by the account root user.
D. Enable multi-factor authentication (MFA) on every account root user in all accounts.
E. Create a custom IAM policy to limit permissions to required actions for the account root user and attach the policy to the account root user.
F. Attach an IAM role to the account root user to make use of the automated credential rotation in AWS STS.