Which feature is indicative of the AK-47?

The AK-47 is notably characterized by its build quality, particularly the use of milled steel in its construction. This feature contributes to the rifle's durability and reliability in various combat conditions. The four-finger groove refers to the design of the trigger guard and grip area, which allows for a firm, comfortable hold when firing the weapon. This design has become iconic and is essential to the AK-47's overall functionality and ergonomic design, recognized worldwide.

In contrast, the other options present features that are not representative of the traditional AK-47. For instance, polymer bodies and adjustable stocks are more commonly associated with modern variations and adaptations of the AK platform rather than the original model. Similarly, a folding stock mechanism is typical of other rifles or specific adaptations, but the classic AK-47 is known for its solid stock. Lastly, the short barrel design does not apply to the AK-47, as it has a standard length barrel that enhances its accuracy and range compared to shorter variants.