Answer:
A locus that shows a 100% association with fur color is known as the "Fur color gene." The Fur color gene is the gene responsible for determining the color of an organism's fur, hair, or skin. Mutations in this gene can lead to variations in fur color. For example, in mice, the agouti gene is located on chromosome 2 and is responsible for determining the color of the mouse's fur. The presence of a dominant form of the agouti gene results in a yellow coat color, while the recessive form of the agouti gene produces a black coat color.