Which two actions should you perform?

You have a Microsoft Exchange Online tenant that has an email domain named contoso.com.

You collaborate with a partner company that has an email domain named adatum.com.

You need to ensure that all the email messages sent to and received from adatum.com are encrypted in transit.

Which two actions should you perform? Each correct answer presents part of the solution. NOTE: Each correct answer is worth one point.
A . Create a connector from adatum.com to Microsoft Office 365 and configure the connector to use SMTP relay.
B. Create a connector from adatum.com to Microsoft Office 365 and configure the connector to require TLS.
C. Create a connector from Microsoft Office 365 to adatum.com and configure the connector to require TLS.
D. Issue S/MIME certificates to all the users in contoso.com.
E. Configure Exchange Online to use direct send to adatum.com.

Answer: B,C