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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All are true regarding endometriosis, except:
assistant
The correct answer is  Whatever the inital genesis of endometriosis its further development depends mainly on estrogen (Option “a”).
 It can occur anywhere in body, Most common site being ovary(Option “d”). 
 Can also involve lungs and pleura (Option “b”). 
 In endometriosis ovary contains tarry dark brown fluid (due to presence of blood pigments like hemosiderin) and cul de sac has yellow brown fluid.

Clear fluid is not seen anywhere, So, Option “c” is incorrect.