which of these would be an example of a ddos attack?an extortion attempt where hackers threaten to reveal names and social security information stolen from medical records databasesoverloading a popular social networking site with inbound messages in order to shut down access to the sitelaunching a targeted phishing campaign on a department of defense or other surveillance networkstealing proprietary data directly from mobile phones using a distributed network of difficult-to-trace online serviceslaunching tough-to-track click-fraud efforts