One of the central arguments of Thomas Barfield's history of Aghanistan is that by the early 1970s a significant gap had opened between the rural population and the central government. Visitors to Afghanistan, he writes (and he was one: he conducted anthropological research among the northern nomadic tribes in the early 1970s), often had the impression that rural Afghanistan was "timeless" and unchanged. But this was not entirely the case. What are some of the examples he gives of changes that had taken place in rural Afghanistan?

A. Declining rates of infant mortality due to increased access to health care professionals.
B. New-generation personal weapons could be in nearly every village (a good example of the revolution wrought by the AK-47 and the widespread availability of cheap effective weaponry).
C. Rising rates of literacy as the government slowly expanded the national educational system.
D. Development projects that led to cotton production in parts of Afghanistan (the Kunduz and Helmand Valley), as well as the creation of a ring road linking Afghanistan's major cities, which affected rural areas in a variety of ways.