What Does the Main Trunk at the Far Left of the "Tree

Question

What does the main trunk at the far left of the "tree of life" represent?
A) all extinct members of the lineage
B) the earliest common ancestor of all the organisms in the tree
C) the most successful members of the lineage
D) the organisms for which most fossils have been discovered

Accepted Answer

The main trunk at the far left of the "tree of life" represents the earliest common ancestor of all the organisms in the tree, also known as the root of the tree.