This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
The presence of Heinz bodies in erythrocytes indicates: 
Select and explain. 
A. Malarial infection, B. Hemoglobin abnormalities, C. Oxidative stress, D. Degraded bacterial forms
C: Oxidative stress
Answer: C: Oxidative stress 
Explanation: Individuals with inherited deficiency of G6PD, an enzyme required for hexose monophosphate shunt for glucose metabolism, fail to develop adequate levels of reduced glutathione in their red cells. 
This results in oxidation and precipitation of hemoglobin within the red cells forming Heinz bodies.

​Mohan H. Textbook of pathology. Jaypee Brothers Medical Publishers; 2015. Edition 7. Page 293