Which of the following solutions is known for its ability to bleach during canal treatment?

The solution that is known for its ability to bleach during canal treatment is hydrogen peroxide. It is a strong oxidizing agent and is commonly used for its bleaching properties. In endodontics, hydrogen peroxide can help in disinfection and the removal of debris from the root canal system. Its oxidative action can also facilitate the breakdown of organic matter within the canal, enhancing the overall disinfection process.

Sodium hypochlorite, although primarily used for its antimicrobial properties and effectiveness in dissolving organic tissue, does not have the same bleaching capability as hydrogen peroxide. While it is also a crucial irrigant used in root canal treatments, its main function is different from that of hydrogen peroxide.

PCP (parachlorophenol) and formocresol are primarily used as antiseptics and in the past, as medicaments in pulp therapy, but they do not possess bleaching characteristics. Their focus is more on the chemical preservation of pulp tissue or as a disinfectant rather than on the bleaching effect during canal treatment.