Bunuel wrote:
Based on induced stem cell techniques akin to those used for research purposes in mice to trigger regeneration of repaired cells, scientists are now well set to exploit stem cell theories into practical cures for a variety of dreaded ailments of man such as cancer, Parkinson’s disease, spinal cord injuries and multiple sclerosis.
A. Based on induced stem cell techniques akin to those used for research purposes in mice to trigger regeneration of repaired cells,
B. Based on induced stem cell techniques akin to those used for research purposes in mice so that the regeneration of repaired cells may be triggered,
C. Using induced stem cell techniques akin to those used for research purposes in mice to regenerate repaired cells,
D. Using induced stem cell techniques akin to those used for research purposes in mice, which triggers regeneration of repaired cells,
E. Using induced stem cell techniques akin to those used for research purposes in mice that trigger regeneration of repaired cells,
the quality of this sentence is above that of many other questions on this forum, the sources of which are unknown. I'll try to briefly explain why I chose C, and why I believe it is the right answer.
First of all, understand the meaning
the sentence starts with a long modifier, then after it comes the subject scientists. Well, scientists are not based on induced stem cell techniques. This is incorrect. Choice B has the same error.
Among C, D, and E:
D - relative pronoun which comes after mice. mice cannot trigger regeneration of repaired cells. it is rather stem cell techniques... that trigger the process..
E - demonstrative pronoun that is not correctly used here, and thus the same meaning error as in choice D can be inferred.
C is the best so far.
P.S. Why trigger is not actually need in C: "to regenerate" -> shows purpose. trigger I believe would have even been redundant here.