An assistant notices the unit is still set for an adult molar exposure while the next patient is a small child. Which single change most directly lowers the child's dose?

Giải thích

Reducing exposure time lowers the total number of photons delivered and is the most direct way to reduce a pediatric patient's dose, consistent with ALARA. Raising kVp increases beam energy rather than reducing dose in this situation. A shorter PID increases divergence and irradiated volume, and removing filtration would allow more low-energy photons into the patient, raising skin dose.