问分词作状语时的主语和主句主语不一样的情况有哪些

chk977

1.请问分词作状语时的主语和主句主语不一样的情况   除了以下作目的状语外
还有有哪些情况？

Five fledgling sea eagles left their nests in western Scotland this summer, bringing to 34 the number of wild birds successfully raised since transplants from Norway
began in 1975.
A) bringing

(B) and brings
(C) and it brings
(D) and it brought
(E) and brought
2.gmat中分词作状语是否一定要用逗号隔开？貌似在别的书又看到直接放到句子背后的 这样貌似有会和定语混淆 让句子结构很乱