In the past two years, the number of campus bookstores offering rentals _____ from a few dozen to

1,500.[ ]

A. jumped

B. had jumped

C. is jumping

D. has jumped

某商店对新购进的一批商品实行简单随机抽样检查，抽样后经计算得：该商品的合格率为98%，抽样平均误差为1%，试在如下条件下分别估计该批商品的合格率：

若给定极限误差为2%。