a.adobe.com has no NS records.
NS records for this zone are defined at adobe.com.
NS records for this zone are defined at adobe.com.
Question and response
Question
dig a.adobe.com. NS
Answer
The response has no answer records.
Authority
adobe.com. 300 SOA exfer-vip-01.corp.adobe.com. hostmaster.adobe.com. 11332 1800 600 2419200 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0