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:
Answer: 
Explanation:
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.
https://technet.microsoft.com/en-us/library/mt712724(v=exchg.150).aspx
MX:IP4 131.107.1.0/24 -all
https://www.spfwizard.net/
https://practical365.com/exchange-server/a-sender-policy-framework-spf-primer-for-exchange-administrators/
IN TXT “v=spf1 ip4:131.107.1.0/24 mx -all”
My previous answer was incorrect, so that SPF generator in my previous link is a bit off. I agree with Mat.
also: https://technet.microsoft.com/en-us/library/3aff33c5-1416-4867-a23b-e0c0c5b4d2be(v=exchg.150)#SPFSyntaxO365
It might actually be “contoso.com -all” at the end instead of MX as per the TechNet link
I agree with Mat
IN TXT “v=spf1 ip4:131.107.1.0/24 mx -all”
Accept all email from IP4 address range 131.107.1.0/24 as well as MX and hard fail all rest.
After further research, I do agree.
After Couple of times research. I thought the correct answer should be as below:
MX:IP4 131.107.1.0/24 -all
I cannot find any example records using ip4 X.X.X.X MX -all
Thanks.
From My understanding, the clue about the first two is in the colon in between them. this means the first two must be “IPV4” and “131.107.1.0/24” respectively.
The SPF wizard that stillme posted above then says that “MX” and “-all” need to be the other arguments in the command.
Which despite being in a slightly different order makes sense, the order of the arguements in this case is probably not important.
The result I got from the SPF generator is:
contoso.com. IN TXT “v=spf1 mx ip4:131.107.1.0/24 -all”
Note where the colon is in the string, it exists only between the IPv4 and the IP address, and every example I’ve found agrees with this, the only other attribute that uses a colon is eg: “include:contoso.com” as you still need the IPV4:131.107.1.0/24, this attribute cannot work in the command that they are looking for.