In pheochromocytoma, not a part the rule of 10 is?

Ans is 'd' i.e. 10% are symptomatic o Pheochromocytomas usually subscribe to a convenient "rule of 10" or "10% tumor"; i.e. 10% of pheochromocytomas are :-1) Bilateral2) Extra-adrenal3) Familial4) Malignant5) Multiple6) Occur in children