A DMARC policy consists of several key components:
Policy (p=): Defines the action to be taken when an email fails DMARC authentication. Options include "none" (monitoring only), "quarantine" (treat suspicious emails with caution), and "reject" (block the email). Subdomain Policy (sp=): Specifies the policy for subdomains. Reporting (rua= and ruf=): Indicates where aggregate (rua) and forensic (ruf) reports should be sent. Alignment (adkim= and aspf=): Specifies the alignment mode for DKIM and SPF, which can be "strict" (s) or "relaxed" (r).