Question and response
Question
dig mail.ctdoc.org. TXT
Answer
mail.ctdoc.org. 1800 TXT "v=spf1 a mx -all"
Authority
ctdoc.org. 1800 NS dns1.registrar-servers.com.
ctdoc.org. 1800 NS dns2.registrar-servers.com.
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0