An organization plans to utilize an on-premise Exchange Server 2010 SP1 environment for employees and a cloud-based Exchange Server 2010 SP1 service for contractors. You need to recommend an anti-spam solution that meets the following requirements:

* Minimize the amount of spam received by the on-premise servers.
* Ensure that internal and external email delivery remains fully functional.

What should you recommend?

A.
Point the MX records for the domain to the on-premise servers. Restrict the allowed IP addresses on the receive connector of the cloud-based servers.

B.
Point the MX records for the domain to the on-premise servers. Configure the allowed IP addresses on the send connector of the cloud-based servers.

C.
Point the MX records for the domain to the cloud-based servers. Restrict the allowed IP addresses on the receive connector of the on-premise servers.

D.
Point the MX records for the domain to the cloud-based servers. Configure the allowed IP addresses on the send connector of the on-premise servers.