Which is the purpose of using a buffer on nails?

Using a buffer on nails primarily serves to smooth the nail surface. Buffing helps to remove any ridges or imperfections on the nail, resulting in a more even texture and a high-gloss finish. This process enhances the overall appearance of the nails, making them look healthier and more polished. Smoother surfaces also allow for nail polish to adhere better and appear more uniform, which is why buffing is often an essential step in the nail care process.

Though other options listed play significant roles in nail care, buffing specifically addresses the smoothing of the nail surface, helping to enhance not only its aesthetic but also its preparation for further treatments like polish application.