Which of the Following Is an Example of Input Fraud

Which of the following is an example of input fraud?

A) A man used desktop publishing to prepare bills for office supplies that were never ordered or delivered and mailed them to local companies. The invoices were for less than $300, an amount that often does not require purchase orders or approvals. A high percentage of the companies paid the bills.
B) Two accountants without the appropriate access rights hacked into Cisco''s stock option system, transferred over $6.3 million of Cisco stock to their brokerage accounts, and sold the stock. They used part of the funds to support an extravagant lifestyle, including a $52,000 Mercedes-Benz, a $44,000 diamond ring, and a $20,000 Rolex watch.
C) The office manager of a Wall Street law firm sold information to friends and relatives about prospective mergers and acquisitions found in Word files. They made several million dollars trading the securities.
D) A fraud perpetrator scanned a company paycheck, used desktop publishing software to erase the payee and amount, and printed fictitious paychecks.