Speaker A: This exercise is really beyond me.
Speaker B: ().

A. When do you think you can work it out

B. Why not come to me

C. When did your teacher give you this math assignment

D. Our math teacher is too hard on us.

社会总供给是指在一定时期内，一国生产部门按一定价格提供到市场的全部产品和劳务的价值总和以及在市场上出售的其他______总量。