The most distinctive feature of pathogenic Entamoeba histolytica on fresh stool examination is -
Presence of active pseudopodia
Erythrophagocytosis
Presence of intracytoplasmic vacuole
Presence of two nucleoli
Ans. is 'b' i.e., Erythrophagocytosis . The presence of red blood cells in the cytoplasm (erythrophagocytosis) is diagnostic of E. histolytica as it is the only intestinal amoeba to exhibit this characteristic.