Which event is a vishing attack? 

Answer options:

A. obtaining disposed documents from an organization
B. using a vulnerability scanner on a corporate network
C. impersonating a tech support agent during a phone call
D. setting up a rogue access point near a public hotspot

C

Reference: https://www.cisco.com/c/en/us/products/security/email-security/what-is-phishing.html#~types-of-phishing-attacks