For Android application development, what is the proper way to set up an Android powered physical device so that it can be used for testing and debugging apps from a development machine?

Introduction / Context:
Using a physical Android device for app development and debugging is common practice because it reveals performance and usability issues that emulators may not show. Interviewers ask this question to check whether candidates know the standard configuration steps required to allow communication between the development machine and the device through the Android tools.

Given Data / Assumptions:
- An Android device and a development machine are available.
- The developer wants to run and debug apps directly on the device.
- Standard Android development tools such as Android Studio and platform tools are installed on the machine.
- The question focuses on high level setup steps rather than every menu name.

Concept / Approach:
To prepare an Android device, the user first enables the hidden developer options menu, which is usually done by tapping the build number a set number of times in the system settings. Within developer options, USB debugging is enabled to allow the device to accept debugging commands from a connected computer. On some desktop operating systems, additional USB drivers are needed so that the device is recognised by the Android Debug Bridge tools. Once drivers and debugging are in place, connecting the device via USB makes it available as a target for running and debugging apps from the integrated development environment.

Step-by-Step Solution:
Step 1: Recall that enabling developer options and USB debugging is mandatory for debugging on a physical device. Step 2: Remember that the development machine may need vendor specific USB drivers for proper recognition. Step 3: Review options and discard any that do not mention these steps. Step 4: Option a describes enabling developer options, turning on USB debugging, installing drivers and connecting via USB. Step 5: Conclude that option a is the correct process for setting up the device.

Verification / Alternative check:
To verify, think of the typical workflow in Android Studio. After performing the steps in option a, the device appears in the list of run targets, and the developer can deploy builds directly. If USB debugging is not enabled or drivers are missing, the device does not appear. This matches practical experience and confirms that option a is correct.

Why Other Options Are Wrong:
Option b ignores the need for developer options and debugging configuration and relies only on installing an unrelated app, which is insufficient. Option c actually prevents debugging by disabling all communication. Option d suggests formatting the device and never connecting it, which is contrary to the goal of app development and testing.

Common Pitfalls:
Common pitfalls include forgetting to authorise the development machine when the device prompts for trust, using low quality USB cables that cause connection drops and not enabling the correct USB mode on the device. Developers should also remember to disable USB debugging when not needed for security reasons on personal devices. Following the proper setup as in option a minimises these issues.

Final Answer:
Enable developer options on the device, turn on USB debugging, install the appropriate drivers on the development machine if required and then connect the device via USB so that it is recognised by the Android development tools.