What is the result of staining lipids (mainly triglycerides) with Sudan IV?

The staining of lipids, particularly triglycerides, with Sudan IV is characterized by its ability to bind to lipid materials, resulting in specific coloration. When Sudan IV is applied to tissue sections containing lipids, it produces a red coloration that highlights the presence of fats. This vibrant red color is a direct indication of the triglycerides and lipids in the sample.

In addition to the staining of lipids, nuclei typically retain a contrasting color, which in this case is black. The black color is often due to the remaining cellular components that do not interact with the Sudan IV dye. This differential staining allows for clear visualization of lipid-rich areas against the darker, contrasting appearance of the nuclei.

Thus, the correct answer accurately describes that lipids stain red with Sudan IV, providing a distinct visual contrast to the black nuclei, making it an effective method for identifying and studying lipid distribution in histopathologic samples.