【正确答案】 A

【答案解析】Here the task is to determine the communal reaction to crime. The write: maintains that the criminal justice system of punishments allows the community to purge itself of its anger, its sense of outrage at the criminal's acts. Thus, it provides a catharsis or purgation for the community.
Remember, in double-blank sentences, go through the answers, testing the first word in each choice and eliminating those that don't fit. In this case, you can readily eliminate Choices B and E: it is unlikely that an essential purpose of the criminal justice system would be the provision of either a disclaimer (denial or disavowal, as in disavowing responsibility for a legal claim) or a document.