<prompt> Which of the following is best for diagnosis of pheochromocytoma?24-hour urinary Vaniyll Mandelic acid24-hour urinary Fractionated Metanephrine24-hour Urinary Hydroxy indole acetic acid24-hour Urinary Hydroxy tryptamine  <response>: Pheochromocytoma Most sensitive screening test for pheochromocytoma- Urinary catecholamines and Vanillyl mandelic acid VMAlevel. Best test for diagnosis of pheochromocytoma- 24 hours plasma fractionated Metanephrine 24 hours urinary plasma fractionated Metanephrine 24 hours urinary hydroxy indole acetic acid is performed for carcinoid tumors 