Your network contains an Active Directory forest named contoso.com. The forest contains an enterprise root certification authority (CA) named CA1. The network contains a server named EX1 that has Exchange Server 2013 installed.
A partner company named ADatum Corporation has an Active Directory domain named adatum.com. The domain contains a server named EX5 that has Exchange Server 2010 Service Pack 2 (SP2) installed. EX5 has a Receive connector that is configured for mutual TLS.
Users in contoso.com plan to send email messages that contain sensitive data to users in adatum.com.
You need to ensure that all of the email messages sent from contoso.com to adatum.com are encrypted by using TLS. The solution must ensure that EX1 and EX5 validate server certificates.
Which three actions should you perform? (Each correct answer presents part of the solution. Choose three.)