问题
单项选择题
大量无色的单一纤维，常完整并具窄管腔（）
A．Bundles of partially lignified fibres with crystal sheaths
B．Numerous colourless single fibres, often whole with narrow lumen
C．Parenchymatous cells，fibres，and vessels
D．Starch granules present，fibres and sclereids absent
E．Fibres with crystal sheath containing calcium oxalate prisms
答案
参考答案：B