请教GWD的题

Rightmelody

1  Sulfur dioxide, a major contributor to acid rain, is an especially serious pollutant because it diminishes the respiratory system’s ability to deal with all other pollutants.

句子正确。有的选项是a specially serious......请问 especially 和 specially 在这如何区分？

2   Were it not for the fusion-powered heat and radiation that rush from its core, instead its own weight would cause a star to collapse.

A.    instead its own weight would cause a star to collapse
B.    instead a star would have collapsed under its own weight
C.    a star would have to be collapsing under its own weight
D.    a star would collapse under its own weight
E.    its own weight would have caused a star’s collapse
请问这道题如何区分B和D

3   Socially and environmentally responsible investing is on the rise:  last year in the United States, over $2 trillion was invested in funds that screen companies according to a variety of criteria such as adherence to labor standards, protection of the environment, and observance of human rights.

according to。。。。。部分划线 请问according在句中什么结构 有点迷糊这题

Linsky

1.especially是尤其的意思强调程度，specially是特别地强调特别性
2.were it not for=if it were not for，所以，if……，instead……
3.现在分词做定语

Rightmelody

再次请教！！！