In a Self-Audit of Your Employee's I-9 Forms, Several Errors

In a self-audit of your employee's I-9 forms, several errors were found. These errors included incomplete sections, questionable documents accepted for verification, and over-documentation. Of the following corrective and prevention strategies, which should you recommend to your employer?

A) Enrollment in E-Verify
B) Requesting updated documents from affected employees
C) Training for employees
D) Recertification of all I-9 forms