Earliest of fetal hea can be detected at:: (A) 6-6.5 weeks, (B) 6.5-7 weeks, (C) 7.1-7.5 weeks, (D) 8 weeks
Answer is A. When the question says - Cardiac activity is earliest detected at it means it's about TVS (Transvaginal sonography),which is seen at 6 weeks. Ref: Callen 4e pg 119,120.