The biggest danger of relying on case-study evidence is that it

it would be d). more resources must be obtained to attain that combination of goods and services

the answer to your question is,

old stone age.

-mabel < 3

an informal structure in a bureaucracy would be something like so-called "office politics". where there's a formal structure set up for the organization, but then an informal subculture as well that has a way of organizing the bureaucracy further. this can be positive because it sets up an added degree of organization, albeit informal, within the bureaucracy.