You need to configure Operations Manager to use mail

Your company has a private cloud that is managed by using a System Center 2012 Operations Manager infrastructure.

The network contains an SMTP host named mail.contoso.com

You need to configure Operations Manager to use mail.contoso.com to send email notifications.

What should you do?

A.
Create a channel

B.
Configure the agent proxy setting.

C.
Create a rule.

D.
Create an internal connector subscription.

Explanation:
How to Enable an Email Notification Channel

To configure alert notifications for System Center 2012 Operations Manager, your first task is to enable a notification channel. This topic describes how to configure a channel that will send alert notifications to subscribers by using email.

http://technet.microsoft.com/en-us/library/hh212914.aspx