In brief
A hard apple without soft sections is a suitable starting point. Consider whether the fruit will be eaten whole, in slices, or as part of a dish.
Useful to know
When choosing apples, look for a firm fruit with a smooth peel, without bruised and softened areas. The University of Iowa recommends refrigerated storage and separation from highly smelling products such as onions. Before eating, rinse under running water. [1]
For immediate use, the apple can be served whole or sliced. The source also gives an idea of slices in rolled whole wheat bread with peanut butter. [1] This is a serving option, not a universal combination for any person or diet.
It is practical when buying to determine the number of whole fruits for individual portions and the number for a common dish. Thus, size has a specific meaning, instead of choosing only the largest fruit.
Do not present each variety as the same for each recipe. Here the directions are for selection, storage and raw serving; the baking behavior requires an additional choice according to the desired structure.
Sources
For further detail and to check the information: