Which of the following is NOT on

题目内容:Which of the following is NOT one of the characteristics of the basic word stock?（ ）
题目选项:
A.All national character
B.Validity
C.Stability
D.Productivity
题目答案:B
题目解析:The basic word stock has obvious characteristics: all national character, stability, productivity, and polysemy. 其中不包含B选项。