Marketo Certified Expert Certification Practice Test 2025 - Free Marketo Practice Questions and Study Guide

The inclusion of SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) as best practices significantly contributes to improving email deliverability. SPF helps verify that the email is sent from an authorized server, reducing the chances of spoofing or phishing attempts. This authentication method tells receiving mail servers which IP addresses are allowed to send emails on behalf of your domain. DKIM adds a digital signature to your emails, allowing recipients to confirm that the email was indeed sent by your domain and hasn't been altered in transit. Together, these protocols enhance the credibility of your email communications, which positively impacts your overall deliverability rates.

In contrast, while HTTPS and SSL are critical for website security and data protection during transmission, they don't directly affect email deliverability. De-duplication is important for list management and engagement but does not inherently improve deliverability metrics. Similarly, Spam Assassin is a spam filter tool that can identify potential spam content, but using it does not directly enhance the deliverability of your emails; rather, it helps with the processing of outgoing emails by checking them against spam criteria. Therefore, focusing on SPF and DKIM is the most effective strategy for ensuring that your emails reach their intended recipients.