The parents of an infant with uncorrected hirschsprung disease are advised to give their child low-residue diet. what choice indicates that the parents need further teaching about the diet?

The answer would be apples.

hirschsprung disease causes some part of the colon unable to move. This makes it prone to obstruction. Low-residue diet will restrict food that has fiber. The aim of this diet is to reduce the feces produced so it won't obstruct the colon. Fruit like apples has high fiber, so its residue is not low. Grains definitely a bad choice as its fiber is very high.