This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
True about chorionic villi biopsy:a) Strongly associated with fascio mandibular defectsb) Done in 10-12 weeksc) Rh immunoglobulin prophylaxis is not necessaryd) Done to diagnose genetic disorders 
Select and explain. 
A. acd, B. bcd, C. abd, D. ab
C: abd
Answer: C: abd 
Explanation: Remember after CVS:

Anti-D immunoglobulin 50 m gm IM should be administered to a Rh-negtive woman.