各位老师好，我在做下面一道给高考考生的模拟题时遇到了这个局面：
Chinese citizens, _____ to enter Maldives visa-free, have already included the country into their list of the most popular tourist destinations.
A. being allowed
B. having been allowed
该题的标准答案是 B。确实，如果从时态的角度分析，应该是先被免签证再有的 included the country into their list of the most popular tourist destinations，选B有时态的理由站得住脚；但是，请各位看下面的这个句子：
Chinese citizens have already included the country into their list of the most popular tourist destinations as they are allowed to enter Maldives visa-free.
从题目的句子来看，红字部分应该是做原因状语，于是把句子改写为上句后，出现了谓语动词用are（一般时态）的情况。
如此一来，该题又为何不可选 A. being allowed 呢？或者说，这样的情况是不能完全凭依时态来判断非谓语动词的使用的特例吗？
