A．because 98 % abortions were carried out before 20 weeksB．because pregnancy can be diagnosed earlier than beforeC．because survival rates among premature babies have improvedD．because the fetal abnormalities can be diagnosed earlier than be fore
A．because 98 % abortions were carried out before 20 weeks
B．because pregnancy can be diagnosed earlier than before
C．because survival rates among premature babies have improved
D．because the fetal abnormalities can be diagnosed earlier than be fore