Which of the following is a diagnostic method for detecting tracheal mites?

Dissection of bees is a diagnostic method for detecting tracheal mites because it allows for a direct examination of the bees' respiratory systems, where these mites reside. By carefully dissecting bees, beekeepers can observe the presence of tracheal mites in the tracheae (the breathing tubes) of the honey bees. This method is particularly effective as it provides clear evidence of the infestation, helping beekeepers determine the level of mite presence and take appropriate management actions.

While visual examination of honeycomb, disease symptom observation, and weight monitoring of hives can provide insights into the overall health of a colony, they do not directly identify tracheal mite infestations. Visual examinations might reveal general signs of distress or weakness in a colony, but the specific presence of tracheal mites requires more invasive techniques like dissection to properly diagnose. Therefore, the dissection method remains the most reliable way to confirm the presence of these pests in bees.