问题如下图：老师你好，可否帮忙解释下C，谢谢
选项：
A. 
B. 
C. 
解释：
a brownfielinvestment. economic infrastructure investment. B is correct. Investing in existing infrastructure asset with the intent to privatize, lease, or sell anlease bathe asset is referreto a brownfielinvestment. economic infrastructure asset supports economic activity aninclus suassets transportation anutility assets. Hospitals are sociinfrastructure assets, whiare focuseon humactivities. 基建投资有两种分类方式 一种按照被投资物的状态即未建/在建(greenfiel或者已经建成(brownfiel, 另外一种按照被投资物的用途 economic or sociuse, economic就是来支持经济活动的，例如铁路，公路 而sociuse就是社会活动的，例如医院、学校等。 题中的hospital对应sociuse，同时又是existing, 所以是brownfiel C为什么不对呢，的确是社会型投资
请问题干如何翻译？
