The word that best describes the action of bile fats is it:

The action of bile fats is best described as emulsifying. Bile, produced by the liver and stored in the gallbladder, contains bile salts which play a crucial role in the digestion of lipids. Emulsification is the process of breaking down large fat globules into smaller droplets, which increases the surface area available for digestive enzymes to act on. This process is essential for effective digestion and absorption of dietary fats in the small intestine.

While digestion is a broader term that encompasses various processes of breaking down food substances, emulsification specifically refers to the way bile interacts with fats. Absorption follows emulsification as the nutrients are taken up into the body's systems, and transportation pertains to the movement of these substances within the body. Therefore, the specific action of bile fats is best encapsulated by the term "emulsifies," as it highlights their role in preparing fats for further digestion and eventual absorption.