多选题Which three statements are true regarding single-row functions？（）AThey can accept only one argument.BThey can be nested up to only two levels.CThey can return multiple values of more than one data type.DThey can be used in SELECT， WHERE， and ORDER BY c
题目
多选题
Which three statements are true regarding single-row functions？（）
A
They can accept only one argument.
B
They can be nested up to only two levels.
C
They can return multiple values of more than one data type.
D
They can be used in SELECT， WHERE， and ORDER BY clauses.
E
They can modify the data type of the argument that is referenced.
F
They can accept a column name， expression， variable name， or a user-supplied constant as arguments.