Which of the following is NOT a standard for maintaining weapon cleanliness?

The correct response highlights that using any available products for cleaning is not a standard for maintaining weapon cleanliness. This is because maintaining weapon cleanliness requires specific cleaning agents that are designed for the materials and functions of firearms. Improper cleaning products can cause damage, affect the performance, or even compromise the safety of the weapon.

In contrast, regular cleaning after each use, ensuring components are free of obstruction, and utilizing proper solvents and lubricants are all recognized standards that contribute to the effective maintenance of firearms. These practices ensure that the weapon functions reliably and safely while extending its lifespan.