IMO Correct answer is A
The analysis, published by several researchers at Yale and Stanford, shows that the recently discovered individual belonged to a previously unknown human lineage, a group that split off from other Native Americans just after — or perhaps just before — they arrived in North America.
Analysis is Singluar so requires a singular verb "shows"
Eliminate D and E
(A) shows that the recently discovered individual belonged to a previously unknown human lineage, a group that split off from other Native Americans just after — or perhaps just before — they arrived
(B) shows the recently discovered individual belonged to a previously unknown human lineage and was a group that split off from other Native Americans just after — or perhaps just before — arriving
and - incorrect parallelism also it is not required. also arriving is incorrect.
(C) shows that the recently discovered individual belonged to a previously unknown human lineage, which was a group that split off from other Native Americans just after — or perhaps just before — and arrived
Meaning error