1、单选题：

Penny Bauer, Chief Financial Officer of Harrison Haulage, suspects irregularities in the payroll system, and orders an inspection of ‘each and every payroll voucher issued since 1 January 2005’. Five per cent of the payroll vouchers contained material errors. This is an example of ________________.

选项：
A:descriptive statistics
B:nominal data
C:nonparametric statistics
D:inferential statistics

答案: 【descriptive statistics】