Which progressive reform allows voters to approve or reject laws passed by the legislature

It would be the Progressive reform of "referendums" that allow voters to approve or reject laws passed by the legislature, since this allows a more direct connection between the voter and the legislature. 

What is this saying? ?

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.