B错误原因能解释一下吗？private cost是什么？

NO.PZ2024010501000005问题如下 Whiof the following statements regarng externalities is most accurate? A.Externalities occur e to environmentor socifactors.B.When externalities are positive, private costs are lower thsocietcosts.C.Internalization of externalities improves companies’ financiperformance. A is correct. Externalities coccur e to environmentfactors, supollution, or socifactors—for example, when companies fail to pa minimum wage. When externalities are positive, private costs are higher thsocietcosts. When externalities are negative, private costs are lower thsocietcosts. Internalization of these externalities coulsignificantly impathe costs anprofits of companies’ procts anservices, affecting their bottom line. 选C的问题是不是说，对于外部性的，改进，有的时候会适得其反所以C是不对的。

NO.PZ2024010501000005 问题如下 Whiof the following statements regarng externalities is most accurate? A.Externalities occur e to environmentor socifactors. B.When externalities are positive, private costs are lower thsocietcosts. C.Internalization of externalities improves companies’ financiperformance. A is correct. Externalities coccur e to environmentfactors, supollution, or socifactors—for example, when companies fail to pa minimum wage. When externalities are positive, private costs are higher thsocietcosts. When externalities are negative, private costs are lower thsocietcosts. Internalization of these externalities coulsignificantly impathe costs anprofits of companies’ procts anservices, affecting their bottom line. 我想外部性这个概念的提出，应该就是针对公司而言的，如果公司没有道德排放污水，劳工待遇不好等，虽然最终反应出来是环境和社会层面的问题，但是occur的缘由是公司，为什么会e to（归因于）环境和社会呢？

NO.PZ2024010501000005 问题如下 Whiof the following statements regarng externalities is most accurate? A.Externalities occur e to environmentor socifactors. B.When externalities are positive, private costs are lower thsocietcosts. C.Internalization of externalities improves companies’ financiperformance. A is correct. Externalities coccur e to environmentfactors, supollution, or socifactors—for example, when companies fail to pa minimum wage. When externalities are positive, private costs are higher thsocietcosts. When externalities are negative, private costs are lower thsocietcosts. Internalization of these externalities coulsignificantly impathe costs anprofits of companies’ procts anservices, affecting their bottom line. Internalization of these externalities coulsignificantly impathe costs anprofits of companies’ procts anservices, affecting their bottom line.外部性内部化能够显著影响公司产品和服务的成本和利润，这里的影响是提高还是降低成本和利润？