Which two valid declarations of a char?()   
A、A. Char ch = “a”;
B、B. Char ch = ‘\’ ‘;
C、C. Char ch = ‘cafe’;
D、D. Char ch = “cafe”;
E、E. Char ch = ‘\ucafe’;
F、F. Char ch = ‘\u10100’;
H、G. Char ch = (char) true;