String data type

We need to define a column that will contain user-defined values. Their length will vary from 10 to 15 characters using English letters, both upper and lower case mixed with numeric digits, with an even distribution of lengths.

Which of these data types will be more efficient?

A. char(15)
B. varchar(15)
C. nchar(15)
D. nvarchar(15)
E. varchar(max)
F. nvarchar(max)

Answer:[B]
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