[单选题]
The elements in the periodic table which lap,lx-o *+mq;czxakfg; f8k5exf d2n 9ck one electron from a filled shelb/hyr x5n7sj589 xsonlb8 e:ml are referhs5eyl 57 mx88j:r 9xn/ sobbnred to as
A. noble gases.
B. halogens.
C. alkali metals.
D. transition elements.
