biz has no MX records.
Question and response
Question
dig biz. MX
Answer
The response has no answer records.
Authority
biz. 900 SOA a.gtld.biz. admin.tldns.godaddy. 1772091972 1800 300 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0