An 8 yr old child suffering from recurrent attacks of polyurea since childhood presents to the paediatrics OPD.On examination the child is short statured vitals and B.P are normal. Serum Creatinine-6 mg%,HCO3 - 16 meq,Na-134,K4.2. On USG bilateral small kidneys are seen.Diagnosis is-

• A. Reflux Nephropathy
• B. Nephronophthisis
• C. Polycystic kidney disease
• D. Medullary cystic kidney disease