This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Gynaecology & Obstetrics
Hydrops fetalis is defined sonographically by 
Select and explain. 
A. One or more fetal effusions, B. Two or more fetal effusions, C. Anasarca, D. Two or more fetal effusions with Anasarca
B: Two or more fetal effusions
Answer: B: Two or more fetal effusions 
Explanation: The term hydrops refers to excessive accumulation of serous fluid in the body, and strictly defined, hydrops fetalis is edema of the fetus. Traditionally, the diagnosis was made after delivery of a massively edematous neonate, often stillborn. With sonography, hydrops has become a prenatal diagnosis. It is defined as two or more fetal effusions or one effusion plus anasarca.(Ref: William's Obstetrics; 25th edition)