In New York City alone,six major institutions have spread up and out into the air space and neighborhoods around them __
问题描述：
In New York City alone,six major institutions have spread up and out into the air space and neighborhoods around them ___ are preparing to do so.
A.which B.or C.so that D.and
Why meaning?
答
In New York City alone,six major institutions(have spread up and out into the air space and neighborhoods around them) ___ (are preparing to do so).
括号内的两部分在成分上是并列的.
意思为：六大主要研究所已经开始向外扩展并进入周围的空间以及邻区,(或者)正在准备这样做.
所依据题意,只能选择or.