A helpdesk technician is explaining Android's application sandbox to a new employee. The employee asks: 'Can App A read files stored by App B?' In a standard non-root Android environment, what is the correct answer?

• A.A. Yes, any app can read any other app's files if it holds the READ_EXTERNAL_STORAGE permission
• B.C. Yes, but only if both apps are from the same developer and share a signing certificate
• C.B. No; each app's private data directory (/data/data/[package_name]/) is assigned a unique Linux UID and filesystem permissions (mode 700) so that other apps running under different UIDs cannot access it
• D.D. No, but apps can request temporary file access through a FileProvider, which grants permanent read access to the requesting app