Iowa Cosmetology Practice Exam 2025 - Free Cosmetology Practice Questions and Study Guide

The primary function of a file during a manicure is to shape and smooth the nails. Filing is an essential step in nail care, as it allows the cosmetologist to create the desired nail shape, whether it be square, oval, or another style. The action of filing not only helps to define the edges of the nails but also smooths any rough or uneven surfaces, leaving the nails looking polished and well-groomed.

While cleaning the nails, polishing them, and pushing back cuticles are all important aspects of nail care, they do not represent the primary purpose of a file. Cleaning nails typically involves using tools like a brush or gentle cleanser, polishing is done using a buffer or polish that adds shine, and cuticle care requires specific implements designed to assist with that area. Thus, the function of a file is specifically focused on the shaping and smoothing process, making the selected answer accurate.