During shaping, which two areas are built up to ensure a flush fit with the metal edges?

The process of shaping involves carefully altering the wood to ensure that it matches and aligns perfectly with the metal components of a firearm. The correct focus on the trigger guard and receiver recesses is crucial because these areas must create a seamless integration between the wooden stock and the metal parts for both aesthetic and functional purposes.

The trigger guard needs to fit neatly into the wood to ensure proper operation and user safety; any misalignment could interfere with the mechanism's functionality. Similarly, the receiver recesses allow the action of the firearm to sit securely within the stock, contributing to the overall stability and alignment. If these areas are not adequately shaped, it could lead to issues with the firearm's performance and user experience.

In contrast, the other options involve different components that may not be as critical for achieving the flush fit required during the shaping process. For instance, while the forend and buttstock are important areas, they do not typically require the same attention to flush fit with respect to the metal components as the trigger guard and receiver recesses do. Therefore, understanding the specific areas that need to be shaped for a proper fit is fundamental in woodworking related to firearms.