What type of tool is commonly used to install strip flooring?

The correct answer is the portable nailer, which is commonly used to install strip flooring because it offers efficiency and speed in driving nails into the wood without requiring manual effort. This tool is specifically designed for flooring installation, allowing carpenters to quickly secure strip flooring boards to the subfloor while ensuring a tight fit. Portable nailers can drive fasteners at a consistent depth, which is crucial for maintaining the integrity and appearance of the flooring.

In contrast, a hammer, while it can be used, is less efficient for this task as it requires more physical effort and precision. A power drill can be used for certain applications but is typically more suited for drilling holes rather than driving nails for flooring. A screwdriver is generally not appropriate for installing strip flooring because it is not designed for driving nails and would take an impractically long time for such a task, making the installation process much less effective.