—What did you do yesterday?

—My brother took two friends of ________ to play chess with us. But I don’t’ know _______ of them.

A．his, all

B．him, both

C．him, either

D．his, either

技术分析认为市场具有不完全性，信息通常是不完整的，不是所有影响证券市场的因素，都必然体现在股票价格的变动上。( )