关于聚类算法与分类算法,下列说法正确的是( ):
A. 聚类算法事先没有类标,而分类算法有类标
B. 聚类是指事先没有标签而通过某种成团分析找出事物之间存在聚集性原因的过程
C. 聚类没有事先定义好类别,类别个数不变,而分类是事先定义好类别,类别数不变
D. 分类是按照某种标准给对象贴标签,再根据标签来区分归类
My dog is very _____. It is safe to touch it if you want to.
A. lucky
B. delicious
C. friendly
D. helpful
My house is ____the two buildings, so we get little sunshine during the day.
A. between
B. among
C. in
D. at
--Henry treats his secretary badly. --Yes. He seems to think that she is the ____important person in the office.
A. little
B. least
C. less
D. most