Which of the following defines animal by-products?

Animal by-products are defined as materials derived from animals that are not the primary product, which is typically meat. These by-products can be utilized in various industries, including food production, pharmaceuticals, cosmetics, and agriculture. The correct answer highlights that animal products are often used as ingredients in non-meal products, indicating a broader understanding of how these materials can be repurposed beyond just direct consumption as food.

The various forms of animal by-products include things like bones, fat, and offal, which can contribute to pet food, biofuels, and even soaps. While animal skins and hides are a type of by-product, and feed supplements may incorporate by-products, these do not capture the full scope of what constitutes animal by-products. Meat products are the primary output from livestock, and therefore, do not fall under the definition of by-products. Understanding this helps to clarify the significance of animal by-products in a variety of applications beyond meat consumption.