Answer:
Common ancestry
Step-by-step explanation:
Variations in health outcomes between racial groups are most strongly tied to common ancestry.
The reason behind this is that each racial group has a different ancestry and a different background. They come from different geographical regions with different cultures and traditions. Therefore every group has a set of health pointers that have evolved and showed themselves due to the variety of different aspects present only in their communities.
Therefore variations of health outcomes differ in each.