—Please write here. I'll come back soon.

—All right. We won't leave ______ you come back.[ ]

A. since

B. until

C. while

与老年人心理生理特征不符合的是（）

A.情绪不稳定

B.老年人解决问题的能力随年龄增长而增长

C.机械记忆能力下降

D.性格方面常表现出固执、刻板