龈上菌斑定义正确的是
A. 未矿化的细菌性沉积物，牢固地黏附于牙面和修复体表面，由细菌构成’
B. 矿化的细菌性沉积物，牢固黏附于牙面和修复体表面，由黏性基质和嵌入其中的细菌构成
C. 部分矿化的细菌性沉积物，牢固黏附于牙面和修复体表面，由黏性基质和嵌入其中的细菌构成
D. 未矿化的细菌性沉积物，牢固黏附于牙面和修复体表面，由黏性基质和嵌入其中的细菌构成
E. 以上均不对
牙髓活力电测验出现假阴性的原因丕包括
A. 事先用过镇痛剂
B. 根尖尚未完全发育
C. 过度钙化
D. 刚受过外伤
E. 未充分隔湿患牙
He was the only person of those clerks that ______ invited to the party.
A. was
B. were
C. is
D. are
As for the winter, it is inconvenient to be cold, with most of _______ furnace fuel is allowed saved for the dawn.
A. what
B. that
C. which
D. such
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