Which of the Following Is an Example of Ponzi Schemes

Which of the following is an example of ponzi schemes?

A) Ursula pays an advance of $500 to Stan Electronics for a microwave oven, which is not delivered to her as promised.
B) Harry assumes his father, Tom's, identity, when swiping Tom's credit card for purchases and signing the receipts.
C) Jenny receives a call from a person selling mobile phones, and purchases a phone by giving her financial information to the unknown caller.
D) Heidi receives an e-mail which offers her an opportunity to share a percentage of millions of dollars.
E) James invests his funds with Tim, who gives James 'high returns', but flees with the remainder money after attracting new investors.