IN has no MX records.
Question and response
Question
dig IN. MX
Answer
The response has no answer records.
Authority
in. 300 SOA ns.trs-dns.com. trs-ops.tucows.com. 1772463659 1800 900 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0