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
Visual prognosis is poor in: 
Select and explain. 
A. Bilateral congenital cataract, B. Unilateral congenital cataract, C. Zonular cataract, D. Cataract pulverulenta
B: Unilateral congenital cataract
Answer: B: Unilateral congenital cataract 
Explanation: Ans. Unilateral congenital cataract