What is the name of the method of measuring the opinions of a large group of people by selecting a subset of the larger group, asking them a set of questions, and generalizing the findings to the larger group?

Which agency was subjected to intense scrutiny by Congress, the press, and the public because it failed to alert the nation to the September 11, 2001, terrorist attacks and misread the existence of weapons of mass destruction in Iraq?

a. the National Reconnaissance Office b. the Central Intelligence Agency c. the Department of Defense d. the National Security Agency

Case studies are unable to

a. generate ideas for theory b. prove or disprove theory c. highlight the limitations of theory d. provide depth on individual cases