| step | query | auth | servers |
|---|
| 1 | 140.38.30.72.in-addr.arpa. | . | (i,k,m,b,l,f,d,e,g,c,h,j,a).root-servers.net. |
| 2 | 140.38.30.72.in-addr.arpa. | in-addr.arpa. | (b,e,d,a,c,f).in-addr-servers.arpa. |
| 3 | 140.38.30.72.in-addr.arpa. | 72.in-addr.arpa. | (r,z,y,t,u,w,v,x).arin.net. |
| 4 | 140.38.30.72.in-addr.arpa. | 30.72.in-addr.arpa. | (ns4,ns2,ns5,ns1,ns3).yahoo.com. |
We pick 
