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
Which of the following is the best marker for intrahepatic cholestasis of pregnancy? 
Select and explain. 
A. AST & ALT (Transaminases), B. Bile Acids, C. Bilirubin, D. Alkaline Phosphatase
B: Bile Acids
Answer: B: Bile Acids 
Explanation: The rise in serum bile acids is sufficient in the third trimester is sufficient to confirm the clinical diagnosis of idiopathic intrahepatic cholestasis of pregnancy which is also accopanied by severe, intractable, generalized itching and sometimes clinical jaundice. Ref: Schiff's Diseases of the Liver By Eugene R. Schiff, Willis C Maddrey, MD, Macp, Willis C. Maddrey, Michael F. Sorrell, Pages 274-276; Medical Disorders in Obstetric Practice By Michael De Swiet, 284 - 286.