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: Medicine
A seven year old asymptomatic girl is found to have persistant hypeension. There is no significant history and urine examination is the following is the most likely cause: 
Select and explain. 
A. Essential Hypeension, B. Renal Parenchymal Disease, C. Renal Parenchymal Disease, D. Coarctation of Aoa
B: Renal Parenchymal Disease
Answer: B: Renal Parenchymal Disease 
Explanation: Answer is B (Renal Parenchymal Disease): Renal Parenchymal Disease is the most contmon cause of hypeension in children and should be considered in the evaluation of all asymptomatic children with hypeension Coarctation of Aoa may present with hypeension in children but this is an uncommon cause and usually presents with a charachteristic finging of blood pressure differential of > 10 mm Hg between upper and lower extremities, systolic hypeension in upper extremity along with decreased or absent femoral pulses Polycystic kidney Disease does not usually present with hypeension in children. Hypeension usually becomes clinically apparent in middle age and hence the condition is also called 'Adult' polycystic kidney disease.