Of the choices given, which one identifies the difference between Android's 'install-time' and 'runtime' permissions, and why did Android 6.0 introduce the runtime model?

• A.Install-time permissions are granted by the Play Store's servers before the download begins (the store applies the manifest against the account's policy), while runtime permissions are granted locally by the operating system at first use: Android 6.0 introduced the runtime model to move the decision off Google's infrastructure, giving every user a device-local choice that no store account setting can override
• B.Install-time permissions (normal level) are granted at APK installation without user interaction; runtime permissions (dangerous level, API 23+) are requested in-context when the feature is first used, allowing users to grant/deny individual permissions - introduced to address the 'all or nothing' install model where users had to grant all permissions or not install the app at all
• C.