Which of the following does the author cite most directly to support his argument in the third paragraph about the importance of exotic goods in the Maya region?

The existence of sophisticated astronomical tables
A

The emergence of a unified Maya kingdom based on new political models
B

The emergence of new systems of writing based on earlier Mesoamerican systems
C

The existence of unified patterns of behavior in warfare, science, and religion
D

The constant presence of diseases or infectious agents within a given geographic area or population group. it may also refer to the usual prevalence of a given disease with such area or group. it includes holoendemic and hyperendemic diseases. a holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic disease). a hyperendemic disease is one that is constantly present at a high incidence and/or prevalence rate and affects all groups equally. so probably family history.