Read the information below:

during the 1820s and 1830s, many people settled in texas and california. the territories were part of mexico. some thought that the united states should annex those territories. the territories were soon independent of mexico. they became part of the united states.

which of following supports this passage?

a) mexico and the united states claimed different national boundaries until the 1840s.
b) mexico did not have very tight control over its northern territories.
c) texas and california needed u. s. military aid to gain independence from mexico.
d) texas and california were only sparsely populated before the 1820s.

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.