Given two different character sets (A and B), which of the following must be true for A to be considered a strict superset of B?（）

A. A must contain all of the characters defined in B
B. A must be Unicode
C. The encoded values in A must match the encoded values in B for all characters defined in B
D. A must be a multibyte character set
E. The encoded values in A must match the encoded values in B for all numeric and alphabetic characters in B