You are the CEO of a large tech company and have just received an angry email that looks like it came from one of your biggest customers. The email says your company is overbilling the customer and asks that you examine the attached invoice. You do but find it blank, so you reply politely to the sender asking for more details. You never hear back, but a week later your security team tells you that your credentials have been used to access and exfiltrate large amounts of company financial data. What kind of attack did you fall victim to?A. A fly phishing attackB. A shark attackC. As a phishing attackD. As a whale attack