b.itconsult-dns.org has no MX records.
Question and response
Question
dig b.itconsult-dns.org. MX
Answer
The response has no answer records.
Authority
itconsult-dns.org. 43200 SOA a.itconsult-dns.net. hostmaster.itconsult.net. 2796 7200 900 1814400 43200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0