Which materials are essential for cleaning a firearm?

The essential materials for cleaning a firearm include cleaning patches, powder solvent, and gun oil, which is reflected in the correct answer.

Cleaning patches are used to remove fouling and debris from the bore of the barrel, ensuring that the firearm operates smoothly and accurately. Powder solvent is necessary to dissolve and remove gunpowder residue left after shooting, as this residue can accumulate and affect the performance of the firearm. Gun oil is crucial for lubricating moving parts of the firearm to prevent rust and ensure proper functioning.

In contrast, the other options do not provide appropriate materials for firearm cleaning. Brushes and wood polish may not be effective for the specific requirements of gun maintenance, while cloth, sandpaper, and adhesive are rarely relevant in this context. Similarly, using cloth, polish, and water does not address the particular needs of cleaning firearms, as water is generally not suitable for cleaning firearms due to the potential for rust.