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: Gynaecology & Obstetrics
Peg cells' are seen in: 
Select and explain. 
A. Vagina, B. Vulva, C. Ovary, D. Tubes
D: Tubes
Answer: D: Tubes 
Explanation: Important Facts about Fallopian Tube:
Length = 4 inches or 10-12 cm.
Parts are :

Interstitium (Intramural): 1.8 cm long and 1 mm diameter (narrowest part). It has no longitudinal muscles, only circular muscles are present.
Isthmus: 3.5 cm long and 2 mm in diameter. (Second narrowest part).
Ampulla: widest and longest part 6-7.5 cm and fertilization occurs here
Fimbria/infundibulum

Histologically:

Fallopian tubes have a unique type of cells called as Peg cells whose function is not known.