As part of a physical audit, Wendie discovers several notes in wastebaskets revealing social security numbers, tax identification numbers, birth dates, and home addresses. Which attack did he execute to discover this issue?

Domain 6: Security Assessment and Testing Practice Questions
Questions from the following topics are included in this domain: 
Designing and validating assessments and tests
Conducting security control testing
Collecting security process data
Analyzing test output data and generating reports 
Conducting and facilitating security audits