You need to design a strategy to meet the company’s requirements for e-mail. What should you do？（）
- AConfigure and publish a certificate template that is suitable for S/MIME, Deploy a Group Policy object （GPO） so that a certificate that is based on this template is automatically issued to all domain users
- BSpecify Group Policy objects （GPOs） and IPSec policies that require all client computers to use Kerberos authentication to connect to mail servers
- CFor each mail server， acquire an SSL server certificate from a commercial CA whose root certificate is already trusted
- DRequire IPSec encryption on all TCP connections that are used to send or receive e-mail message