【名词&注释】
体外受精(in vitro fertilization)、结缔组织(connective tissue)、同源人工授精(artificial insemination by husband)、异源人工授精(artificial insemination by donor)、无性生殖(asexual reproduction)
[单选题]与后腭杆对比,前腭杆的特点为
A. 厚而宽,厚度约1.5~2mm,宽度约3.5mm
B. 薄而宽,厚度约1~1.5mm,宽度约3~3.5mm
C. 薄而宽,厚度约1mm,宽度约8mm
D. 薄而宽,厚度约0.5mm,宽度约5mm
E. 厚而宽,厚度约2mm,宽度约5mm