The concept of cultural diffusion will most likely be used by historian to explain

The concept of cultural diffusion will most likely be used by historian to explain the common use of the lion in Christianity and the use of the lion in indigenous African religions.

Explanation:

Cultural diffusion describes the spread of one culture's practices, beliefs, and/or items, like food, music, or tools. This spread can be among members of the same culture or to completely different cultures around the world. Cultural diffusion is why many cultures around the world share similarities.

porter is writing economic history because he is focusing on the cost of developing vaccines.