这个题的红字解释是什么意思呢？

mike125615212

Citing therecent increase in earnings by several computer companies, economists feel thata cycle has begun in which personal computer users, especially corporateconsumers, are replacing their PC’s with more powerful models.
in which定语从句后置，避免头重脚轻
A.   ！a cycle has begun in which personal computer users  
B.   a cycle for personal computer users hasbegun in which they
C.   there is a cycle beginning for personalcomputer users
D.   it is the beginning of a cycle for personalcomputer users
E.    personal computer users are in the beginningof a cycle when they

mike125615212

木有人~