A user's Android device begins showing advertisements over other apps and the battery drains rapidly. The security analyst discovers an app requesting SYSTEM_ALERT_WINDOW and FOREGROUND_SERVICE permissions installed 3 weeks ago. What malware category best describes this and what is the primary mechanism?

• A.C) This is ransomware encrypting the device; the pop-up ads are ransom payment portals.
• B.B) This is banking malware performing overlay attacks on financial apps; the advertisements are cover for credential theft.
• C.A) This is HiddenAds / aggressive adware: SYSTEM_ALERT_WINDOW allows drawing full-screen overlay ads over any app, and FOREGROUND_SERVICE keeps the ad-serving process alive in the background with higher OS scheduling priority. The app generates ad revenue by displaying ads the user cannot easily dismiss, while the persistent foreground service prevents the OS from killing the ad worker.
• D.D) The device has a SIM card issue; the battery drain and pop-ups are caused by carrier background processes, not malware.