Exam 70-345 topic 1 question 42 discussion

DRAG DROP -
You need to configure the Sender Policy Framework (SPF) for a domain named contoso.com to ensure that only the following senders are authorized to send email for contoso.com:
✑ Hosts listed in the contoso.com MX records
✑ IP addresses in the 131.107.1.0/24 subnet
How should you configure the DNS record for the SPF? To answer, drag the appropriate values to the correct targets. Each value may be used once, more than once, or not at all. You may need to drag the split bar between panes or scroll to view content.
Select and Place:

Suggested Answer:
A typical SPF TXT record for Office 365 has the following syntax: v=spf1 [<ip4>|<ip6>:<IP address>] [include:<domain name>] <enforcement rule>
Enforcement rule is usually one of the following:
-all
Indicates hard fail. If you know all of the authorized IP addresses for your domain, list them in the SPF TXT record and use the -all (hard fail) qualifier. Also, if you are only using SPF, that is, you are not using DMARC or DKIM, you should use the -all qualifier. We recommend that you use always this qualifier.
The meet the requirement, "Hosts listed in the contoso.com MX records", we need to use the MX option in the SPF record.
References:
https://technet.microsoft.com/en-us/library/mt712724(v=exchg.150).aspx