Mrs. Wilson, a primigravida, was admitted to the hospital at 12 weeks’ gestation. She is complaining of abdominal cramping, exhibits bright red vaginal spotting without cervical dilation. The nurse determines that the client is most likely experiencing which of the following types of abortion

A. Complete.
B. Threatened.
C. Inevitable.
D. Misse

如图为元素周期表第三周期的局部．据此判断下列说法中正确的是（　　）

A．它们都属于金属元素

B．1个铝原子的质量是26.98g

C．硅元素的原子序数为l4

D．镁元素的相对原子质量为24.31