Exam MS-100 topic 2 question 65 discussion

Correct - MX Records 1.) Add Custom Domain 2.) Move Mailboxes 3.) Update DNS Records (MX, SPF) to point to EXO https://docs.microsoft.com/en-us/exchange/mail-flow-best-practices/manage-mail-flow-for-multiple-locations#manage-mail-flow-where-some-mailboxes-are-in-microsoft-365-or-office-365-and-some-mailboxes-are-on-your-organizations-email-servers

Was in my exam today 05/08/22.

D is the correct answer as in order to use Microsoft Defender for Office 365 you must route all mail via Microsoft Exchange Online meaning the MX records must be updated to point to Exchange Online. This means D is the only sensible answer

Answer is D

The Microsoft learning harps on using them for spam. They give examples to point the MX record to them, and then have a connector to send the mail to onsite exchange. That's why D was chosen for the answer.

Correct answer in my opinion is updating MX record. EOP provides built-in malware and spam filtering capabilities that help protect inbound and outbound messages from malicious software and help protect your network from spam transferred through email. This action alone can help meet the requirement specified in the question.

Ref: https://docs.microsoft.com/en-us/exchange/transport-routing If you change your MX record to point to the Exchange Online Protection service in Microsoft 365 or Office 365: This is the recommended configuration for hybrid deployments. All messages sent to any recipient in either organization will be routed through the Exchange Online organization first. A message addressed to a recipient that's located in your on-premises organization will be routed first through your Exchange Online organization and then delivered to the recipient in your on-premises organization. This route is recommended if you have more recipients in your Exchange Online organization than in your on-premises organization. This configuration option is required for Exchange Online Protection to provide scanning and blocking for spam.

The answer is not create an MX record. In the question, that is already done as you are migrating the mailboxes already. The question asks specifically about preventing Spam. This is done with a SPF TXT record. https://docs.microsoft.com/en-us/microsoft-365/admin/get-help-with-domains/create-dns-records-at-any-dns-hosting-provider?view=o365-worldwide

In order for EOP to be applied, email must be routed through M365 Exchange. Of the available options, only updating the MX record would do this. Even though the question does not allude to the current MX configuration but is assumed due the existing config being Hybrid.