Final answer:
A donor with visible signs of jaundice would be rejected from blood donation because it indicates an elevated concentration of bilirubin, which could suggest liver dysfunction or other diseases, making the blood unsafe for transfusion.
Step-by-step explanation:
Among the physical examination results that may cause a donor to be rejected from blood donation, the answer is D) Visible signs of jaundice. Jaundice, or icterus, is a condition that indicates the accumulation of hemoglobin degradation products, such as bilirubin, in the blood and peripheral tissues, causing a yellow coloration of the skin and other tissues. With normal bilirubin levels being less than 1 mg/100ml, an elevated concentration (hyperbilirubinemia) suggests that the liver is not functioning properly to eliminate these substances. This is significant in the blood donation process, as it can be indicative of underlying diseases or conditions that could make the donated blood unsafe for transfusion to recipients.