Which of the Following Is True of Robert Putnam's Observations

Which of the following is true of Robert Putnam's observations on social capital?

A) Putnam observed that the practice of free market principles is essential for a moral life.
B) Putnam observed that a sharp rise was seen in league bowling from 1980 to 2000,although the number of bowlers decreased by about 10 percent.
C) Putnam observed that virtually every measure of social interaction fell significantly from roughly 1975 to 2000.
D) Putnam observed that only three categories of government were necessary: the police,the armed services,and the law courts.