If two organisms are in the same clade, they share a common ancestor.
What do you mean by clade?
>A clade is a group of organisms that consists of a common ancestor and all its lineal descendants, and represents a single "branch" on the "tree of life"
The correct answer is -
They share a common ancestor.
Evidences for the common descent of living organisms (that is whether they have evolved from the same ancestor) have been elucidated through phylogenetic tree.
A clade (also called monophyletic group) is considered as a group of individual organisms, with common ancestor and its descendants. It indicates a single "branch" on the phylogenetic tree (also known as "tree of life).
Therefore, two organisms belonging to the same clade share common ancestor.