A woman admitted through the emergency department delivered only 30 minutes after arriving at the ...

A woman admitted through the emergency department delivered only 30 minutes after arriving at the hospital. She stated that her contractions had begun about 2 hours earlier and rapidly became more frequent and intense.
 
  Which statement best defines this brief labor?
  a. Because this was a precipitate labor, it could have resulted in fetal hypoxia or intracranial hemorrhage and maternal trauma.
  b. This was probably a postterm labor, which typically progresses very rapidly with little fetal or maternal risk.
  c. Hydramnios is a common cause of very rapid labor as a result of overdistention of the uterus.
  d. Women who have had previous cesarean births are at risk of uterine rupture following rapid labor.