Inspect the TXT strings on any domain — SPF, DKIM, DMARC, verification tokens.
TXT records carry free-form text used by email authentication (SPF, DKIM, DMARC) and ownership verification (Google, Microsoft, etc.). Each string is shown separately; long DKIM keys may be split across multiple strings.
google.com TXT → v=spf1 …An SPF policy listing which servers may send mail for the domain.
One domain can hold SPF, several DKIM selectors, DMARC and verification tokens at once.
The domain has none published — common for domains that do not send mail.