<prompt> 23 year old Female presents with 42 days of amenorrhea and vaginal spotting. Which of the following is the most useful diagnostic test?Transvaginal USGUrine pregnancy testBeta HCGSerum Progesterone  <response>: In this case, firstly we will do TVS to look for G-sac and cardiac activity to rule in or rule out Pregnancy. A TVS would also confirm bility, since the patient has presented with bleeding pv which could be a sign of an aboion. Method Gestational Sac Cardiac activity TVS 4 weeks 5 weeks TAS 5 weeks 6weeks 