Exam SEC504 topic 1 question 92 discussion

Adam works as a Security administrator for Umbrella Inc. He runs the following traceroute and notices that hops 19 and 20 both show the same IP address.
172.16.1.254
(172.16.1.254) 0.724 ms 3.285 ms 0.613 ms 2 ip68-98-1761.nv.nv.cox.net
(68.98.176.1) 12.169 ms 14.958 ms 13.416 ms 3 ip68-98-176-1.nv.nv.cox.net
(68.98.176.1) 13.948 ms ip68-100-0-1.nv.nv. cox.net
(68.100.0.1) 16.743 ms 16.207 ms 4 ip68-100-0-137.nv.nv.cox.net
(68.100.0.137) 17.324 ms 13.933 ms 20.938 ms 5
68.1.1.4
(68.1.1.4) 12.439 ms 220.166 ms 204.170 ms 6 so-6-0-0.gar2.wdc1.Level3.net
(67.29.170.1) 16.177 ms 25.943 ms 14.104 ms 7 unknown.Level3.net
(209.247.9.173) 14.227 ms 17.553 ms 15.415 ms "Examkiller" - 8 so-0-1-0.bbr1.NewYork1.level3.net
(64.159.1.41) 17.063 ms 20.960 ms 19.512 ms 9 so-7-0-0.gar1. NewYork1.Level3.net
(64.159.1.182) 20.334 ms 19.440 ms 17.938 ms 10 so-4-0-0.edge1.NewYork1.Level3. net
(209.244.17.74) 27.526 ms 18.317 ms 21.202 ms 11 uunet-level3-oc48.NewYork1.Level3.net
(209.244.160.12) 21.411 ms 19.133 ms 18.830 ms 12 0.so-6-0-0.XL1.NYC4.ALTER.NET
(152.63.21.78) 21.203 ms 22.670 ms 20.111 ms 13 0.so-2-0-0.TL1.NYC8.ALTER.NET
(152.63.0.153) 30.929 ms 24.858 ms 23.108 ms 14 0.so-4-1-0.TL1.ATL5.ALTER.NET
(152.63.10.129) 37.894 ms 33.244 ms 33.910 ms 15 0.so-7-0-0.XL1.MIA4.ALTER.NET
(152.63.86.189) 51.165 ms 49.935 ms 49.466 ms 16 0.so-3-0-0.XR1.MIA4.ALTER. NET
(152.63.101.41) 50.937 ms 49.005 ms 51.055 ms 17 117.ATM6-0.GW5.MIA1.ALTER.NET
(152.63.82.73) 51.897 ms 50.280 ms 53.647 ms 18 Examkillergw1. customer.alter.net
(65.195.239.14) 51.921 ms 51.571 ms 56.855 ms 19www.examkiller.com
(65.195.239.22) 52.191 ms 52.571 ms 56.855 ms 20 www.examkiller.com
(65.195.239.22) 53.561 ms 54.121 ms 58.333 ms
Which of the following is the most like cause of this issue?