A physical penetration tester needs to get inside an organization's office and collect sensitive information without acting suspiciously or being noticed by the security guards. The tester has observed that the company's ticket gate does not scan the badges, and employees leave their badges on the table while going to the restroom. Which of the following techniques can the tester use to gain physical access to the office? (Choose two.)

A. Shoulder surfing
B. Call spoofing
C. Badge stealing
D. Tailgating
E. Dumpster diving
F. Email phishing