In a recently conducted study, Harvard Scientists have linked a molecu

A. In a recently conducted study, Harvard Scientists have linked a molecule to PGC-1 alpha FNDC5, a protein that enhances the expression of brain-health, not only as promoting the development of new nerves and synapses in the hippocampus of the adult brain, but also preserving existing brain cells. not only as --- but also preserving – un//

B. In a recently conducted study by Harvard Scientists, a molecule PGC-1 alpha FNDC5, a protein enhancing the expression of brain-health, not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells.--- In as survey, the protein promotes --- wrong meaning.

C In a recently conducted study by Harvard Scientists, the researchers have linked a molecule to PGC-1 alpha FNDC5, a protein that enhances the expression of brain-health, saying that it not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells. ---- Correct choice

D Linking a molecule PGC-1 alpha to FNDC5, a protein that enhances the expression of brain-health, Harvard Scientists claim that the factor not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells in a recently conducted study. 1. Wrong word order. In a recently conducted survey modifies brain cells. 2. The introductory modifier modifies ‘a protein’ changing the meaning.

E In a recently conducted study by Harvard Scientists, which linked a molecule PGC-1 alpha to FNDC5, a protein enhancing the expression of brain-health, it not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells -- 1.Which modifies the Scientists, 2. It is redundant 3. study linked the molecule; altered intent.

I am quite surprised that "saying" and "it" in C are acceptable. I take notice that "saying" often is present in a right answer, especially if the word follows a commas to modify the preceding clause.
B looks more attractive, but B is a trap.

In a recently conducted study, Harvard Scientists have linked a molecule to PGC-1 alpha FNDC5, a protein that enhances the expression of brain-health, not only as promoting the development of new nerves and synapses in the hippocampus of the adult brain, but also preserving existing brain cells.


A. In a recently conducted study, Harvard Scientists have linked a molecule to PGC-1 alpha FNDC5, a protein that enhances the expression of brain-health, not only as promoting the development of new nerves and synapses in the hippocampus of the adult brain, but also preserving existing brain cells. Parallelism error- not only as X but also Y

B. In a recently conducted study by Harvard Scientists, a molecule PGC-1 alpha FNDC5, a protein enhancing the expression of brain-health, not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells. No linking of molecule- changed the sentences entire meaning

C. In a recently conducted study by Harvard Scientists, the researchers have linked a molecule to PGC-1 alpha FNDC5, a protein that enhances the expression of brain-health, saying that it not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells. Correct- paralellism- ok, antecedent to it -ok, conveys clear meaning of the sentence

D. Linking a molecule PGC-1 alpha to FNDC5, a protein that enhances the expression of brain-health, Harvard Scientists claim that the factor not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells in a recently conducted study.
Changed the meaning of the sentence
E. In a recently conducted study by Harvard Scientists, which linked a molecule PGC-1 alpha to FNDC5, a protein enhancing the expression of brain-health, it not only promotes the development of new nerves and synapses in the hippocampus of the adult brain, but also preserves existing brain cells