What can happen if you file against the growth of a nail?

Filing against the growth of a nail can lead to splitting, which is why this option is the correct choice. When a nail is filed in the opposite direction of its natural growth, it disrupts the structural integrity of the nail plate. This can weaken the layers of the nail, making them more prone to breakage and splits. Proper filing techniques involve moving the file in the same direction as the nail grows, which helps maintain its strength and prevents damage.

While options such as waves and pitting might be associated with other conditions or improper techniques, they do not directly result from the act of filing against the nail's growth direction. Stronger nails, on the other hand, would not be a consequence of filing incorrectly; rather, they are a result of proper nail care and growth practices. Thus, the consequence of splitting accurately reflects the risks associated with improper filing techniques.