c.tldns.godaddy has no MX records.
Question and response
Question
dig c.tldns.godaddy. MX
Answer
The response has no answer records.
Authority
tldns.godaddy. 900 SOA a.tldns.godaddy. admin.tldns.godaddy. 1772231846 1800 300 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0