HOTSPOT
You are the Exchange Online administrator for an organization. The organization migrates all users
to Exchange Online. An employee works for a partner organization named Contoso, Ltd. The
employee uses the email alias employeel©contoso.com.
Users report that over the past week, they have not received email messages from
[email protected].
You need to trace email messages that originate from [email protected] to users inside your
organization.
In the message trace window, which two settings should you configure? To answer, select the
appropriate objects in the answer area.
Answer: 
Explanation:
Different asnwer here: http://www.aiotestking.com/microsoft/which-two-settings-should-you-configure-12/
this answer is wrong sender is correct source
https://technet.microsoft.com/en-us/library/jj200712(v=exchg.150).aspx
Key word from the question is “originate”, therefore the answer should be Sender and not Recipient.
“You need to trace email messages that originate from [email protected] to users inside your
organization.”