患者，男，55岁，因患牙周病拔除余留牙，三月后做全口义齿修复。二年后，患者常因说话和吃饭脱落，来院修理，造成这一现象的主要原因是（）

A.义齿基托伸展范围不够

B.义齿基托伸展范围过长

C.没有缓冲颊、舌、唇系带区基托边缘

D.牙槽嵴吸收，基托与口腔组织面不贴合

E.前伸、侧向运动时，有干扰

The tools and techniques of quantitative risk analysis are______．

A．contracting，contingency planning，alternative strategies，and insurance

B．interviewing，historical results，workarounds，and additional response development

C．checklists，damage control reports，standard allowances, and inspection

D．data gathering and representation techniques，and quantitative risk analysis and modeling techniques