Viral infection that is least transmitted transplacentally:
High-Yield Explanation
Ans. is 'a' i.e., Hepatitis B (Ref: Arora Microbiology, 3rd/e, p. 702)Rubella and HSV are teratogenic virus, so their transplacental transmission is expected to be high, HIV have 30% transplacental transmission but HBV is least transmitted transpalcentally.