属于下颌骨外面的结构为

A．颏结节

B．上下颏棘

C．二腹肌窝

D．下颌舌骨肌线

E．舌下腺窝

Oxytocin (Pitocin) is administrated to a client during labor. Which of the following is the most serious adverse effect associated with oxytocin（）

A. Water intoxication.

B. Tetanic contractions.

C. Elevated blood pressure.

D. Early decelerations of fetal heart rate.