Final answer:
The most likely individual to have anemia is the 81-year-old woman with chronic heart failure due to decreased production of EPO, age-related risks, and potential nutrient deficiencies.
Step-by-step explanation:
Among the individuals listed, the one who is most likely to have anemia is B) An 81-year-old woman who has chronic heart failure. This is due to the fact that chronic illnesses, such as heart failure, can contribute to anemia. Both chronic kidney disease and chronic heart failure are associated with decreased production of erythropoietin (EPO), a hormone necessary for red blood cell production. As people age, they are also at greater risk of developing nutrient deficiencies and medical conditions that can lead to anemia.
While the 13-year-old girl who has just experienced menarche is also at risk due to the possibility of iron deficiency anemia from menstruation, the elderly woman with chronic heart failure is at a higher risk due to the potential combination of factors like malnutrition, chronic inflammation, and reduced renal function which often accompany heart failure.
Iron-deficiency anemia is indeed the most common type, particularly in adolescent girls and women of childbearing age due to menstrual blood loss. However, the severity and chronic nature of heart failure in the elderly patient typically presents a greater risk for the development of anemia.