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: Ophthalmology
Persistent Primary Hyperplastic Vitreous (PHPV) is associated with: 
Select and explain. 
A. Patau syndrome, B. Edward syndrome, C. Trisomy 14, D. Downs syndrome
A: Patau syndrome
Answer: A: Patau syndrome 
Explanation: Though Persistent Primary Hyperplastic Vitreous (PHPV) is found to be associated with many chromosomal abnormalities, the most common trisomy associated with it is Trisomy 13 (Patau Syndrome). Trisomy 18, 21 are also in rare occasions associated with PHPV. Ref: Pediatric Ophthalmology and Strabismus, By Kenneth Weston Wright, Page 1055/ Springer, 2003; Paediatric Opthalmology by Pamella Gallin (2000), Page 85; Rudolph Paediatrics 21st Edition, Page 2390