This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: parasitology, Subject name: Microbiology
All are seen in cyst of E.Histolytica except - 
Select and explain. 
A. Glycogen mass, B. Chromatid bars, C. Eccentric nucleus, D. Refractile nucleus
D: Refractile nucleus
Answer: D: Refractile nucleus 
Explanation: Entamoeba histolytica. (A) Trophozoite; (B) Precystic stage; (C) Uninucleate cyst; (D) Binucleate cyst; (E) Mature quadrinucleate cyst; 1--Ectoplasm; 2--Endoplasm; 3--Ingested erythrocytes; 4--Pseudopodium; 5--Nucleus; 6--Chromidial bar; 7--Glycogen mass in mature cyst- nuclear structure similar to trophozoite quadrinucleate glycogen mass and chromatid bars disappeared TEXTBOOK OF MEDICAL PARASITOLOGY,BAVEJA,3RD EDITION,PAGE NO 16