What is a common characteristic of macrocytic anemia?

Macrocytic anemia is characterized primarily by the presence of large red blood cells, known as macrocytes, which typically result from disruptions in DNA synthesis. Conditions that lead to macrocytic anemia often involve deficiencies in vitamin B12 or folate, both of which are essential for proper red blood cell formation. When these nutrients are insufficient, red blood cell precursors cannot divide appropriately, leading to the development of larger than normal cells.

In contrast to the other options, which describe different conditions affecting red blood cell morphology, the identification of large red blood cells is central to diagnosing macrocytic anemia. The presence of small, fragmented, or colorful red blood cells would suggest other forms of anemia, such as microcytic or hemolytic anemias respectively. Therefore, the distinguishing feature of macrocytic anemia is indeed the large size of the red blood cells, affirming that the choice highlighting this characteristic is the correct one.