Which of the following approaches to increasing the signal may lead to an increase in scatter reaching the IR?

Increasing the kilovoltage peak (kVp) in digital radiography enhances the quality of the x-ray beam by increasing its energy. This higher energy allows for greater penetration through tissues, resulting in improved image contrast and a higher signal being received by the image receptor (IR). However, one consequence of raising the kVp is that it also increases the amount of scatter radiation produced within the patient's body.

As the energy of the x-ray photons increases, the likelihood of Compton scattering also rises; this leads to more scatter photons being generated. These scatter photons can then reach the IR, contributing to a decrease in image contrast and potentially affecting the diagnostic quality of the radiographic image.

The other approaches mentioned have different impacts on scatter and image quality. Decreasing field size generally reduces the volume of tissue irradiated, which can, in turn, reduce scatter. Utilizing a grid helps to absorb some of the scatter radiation before it reaches the IR, thus enhancing image quality. Increasing the source-to-image distance can also help reduce the effects of scatter by allowing more distance for scatter photons to diffuse before reaching the IR.