单项选择题

A. 4-O-ß-D-吡喃葡糖苷基-D-吡喃葡糖
B. 4-O-α-D-吡喃葡糖苷基-D-吡喃葡糖
C. 4-O-α-L-吡喃葡糖苷基-L-吡喃葡糖
D. 4-O-ß-L-吡喃葡糖苷基-L-吡喃葡糖