Final answer:
Hemosiderin has the ability to reduce silver due to its iron content, whereas bile, containing bilirubin, does not participate in such reduction reactions. Option d.
Step-by-step explanation:
Out of the listed pigments, hemosiderin is the substance that will reduce silver because it contains iron, which can donate electrons to reduce other compounds. Hemosiderin is a pigment that is derived from the breakdown of hemoglobin. The other substances listed, such as carbon, formalin, and bile, do not have this property.
Bile, for instance, is composed of bilirubin, which is a yellow pigment that is processed in the liver, secreted into the bile, and then broken down in the intestines to form stercobilin, a brown pigment that gives stool its characteristic color.
Although bile pigments are a product of the breakdown of hemoglobin, they are not involved in reduction reactions like those required to reduce silver. So option d