【名词&注释】
体外受精(in vitro fertilization)、覆盖义齿(overdenture)、有利于(beneficial to)、全口义齿固位(retention of complete denture)、同源人工授精(artificial insemination by husband)、大连接体(major connector)、异源人工授精(artificial insemination by donor)、牙槽嵴顶(alveolar ridge crest)、艾滋病监测(aids surveillance)、无性生殖(asexual reproduction)
[单选题]有利于全口义齿固位的解剖形态是
A. 后堤区较窄
B. 牙槽嵴低平
C. 黏膜薄
D. 腭盖平坦
E. 系带附着近牙槽嵴顶(alveolar ridge crest)