GWD 9-2 怎么都不知道怎么分析啊

As the honeybee’s stinger is heavily barbed, staying where it is inserted, this results in the act of stinging causing the bee to sustain a fatal injury.

1. As the honeybee’s stinger is heavily barbed, staying where it is inserted, this results in the act of stinging causing
2. As the heavily barbed stinger of the honeybee stays where it is inserted, with the result that the act of stinging causes
3. The honeybee’s stinger, heavily barbed and staying where it is inserted, results in the fact that the act of stinging causes
4. The heavily barbed stinger of the honeybee stays where it is inserted, and results in the act of stinging causing
5. The honeybee’s stinger is heavily barbed and stays where it is inserted, with the result that the act of stinging causes

答案选C,但我怎么都不知道怎么分析啊？为什么其他的不对？找不到头绪啊!!!

Why is D not correct?

Thanks!

1. The heavily barbed stinger of the honeybee stays where it is inserted, and results in the act of stinging causing

 1 and result 平行的话，前面不用逗号隔开；

2 it 的指代有修饰歧义的嫌疑。