这个知识点是在哪里？
问题如下图：
选项：
A. 
B. 
C. 
解释：
NO.PZ2018070201000049 问题如下 Baseon trang costs, whiof the following is least likely to impacteliquity? A.Stock's trang price. B.The fferenbetween the buying prianselling price. C.brokerage commissions C is correct. The cost of trang hthree main components—brokerage commission, biask sprea anpriimpact—of whiliquity affects the latter two. Brokerage commission is usually negotiable baseon the orr size. The cost of trang hthree main components—brokerage commission, biask sprea anpriimpact—of whiliquity affects the latter two. Brokerage commission is usually negotiable baseon the orr size交易成本 三个主要部分，经纪人佣金，买卖价差，价格影响。流动性影响后面2个，经纪人佣金和订单大小有关。交易成本有佣金我理解，但买卖价差，价格影响指的是什么？交易成本不是交易过程中附带的吗？而买卖的价格高低不该是sales价格吗？怎么能归于交易成本呢？流动性和交易成本又是什么关系呢？这个知识点网课里有吗？学完了这一章来做这个题完全没见过这个知识点啊
NO.PZ2018070201000049 问题如下 Baseon trang costs, whiof the following is least likely to impacteliquity? A.Stock's trang price. B.The fferenbetween the buying prianselling price. C.brokerage commissions C is correct. The cost of trang hthree main components—brokerage commission, biask sprea anpriimpact—of whiliquity affects the latter two. Brokerage commission is usually negotiable baseon the orr size. 交易佣金，不也应该是流动性越差，佣金越高吗？
NO.PZ2018070201000049 问题如下 Baseon trang costs, whiof the following is least likely to impacteliquity? A.Stock's trang price. B.The fferenbetween the buying prianselling price. C.brokerage commonssions C is correct. The cost of trang hthree main components—brokerage commission, biask sprea anpriimpact—of whiliquity affects the latter two. Brokerage commission is usually negotiable baseon the orr size. 感觉这个是不是别的章节的
NO.PZ2018070201000049 中介佣金怎么不影响！！我怎么去理解呢。。。。如果这家券商万一佣金率我就选择这家～另外一家万5我肯定就不选择～不选择的那家不就流动性就差了吗！都没人去了。。。怎么不影响流动性呢。。
老师，请问这个知识点是在课件里什么地方呢？我没有在portfolio章节中看到啊。
