b.tld.lt has no MX records.
Question and response
Question
dig b.tld.lt. MX
Answer
The response has no answer records.
Authority
lt. 900 SOA a.tld.lt. hostmaster.domreg.lt. 1771830014 3600 300 604800 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0