Parkinson's Disease: ONE FUNCTION OF THE THIRD PARAGRAPH..

[iamreadyforaction]

One function of the third paragraph of the passage is to

a.highlight the many similarities between yeast cells and mammalian nerve cells

b.explain in detail the methods used to conduct a genetic screen in yeast cells

c.further explain the roles of various cellular components of yeast cells

d.identify the genes in yeast cells and mammalian nerve cells that work to reverse the toxic levels of alpha-synuclein

b..clarify the relevance of genetic testing in yeast cells to the search for a new treatment for Parkinson’s disease

I would have picked the answer D, but chose not to solely because of the word "clarify". Because the GMAT is very specific with the words they choose in their answer choices, the word "clarify" did not seem fit. I do not believe that there was anything to clarify about the 'relevance of genetic testing' because the author of the passage does not start to talk about the gene research until the third paragraph. I feel like it is misleading to phrase the question "one function of the third paragraph", and correct the answer choice is "clarify something" although the thing it is clarifying is within the paragraph in question. Something only needs to be clarified if there was ambiguity at least a sentence beforehand. So would someone give me some clarification?

[jnelson0612]

We're happy to help, but we need you to actually post the reading comp passage. Please edit your message to include the passage--thanks!

[ankur.mittal09]

Symptoms of Parkinson’s Disease, such as tremors, are thought to be caused by low dopamine levels in the brain. Current treatments of Parkinson’s disease are primarily reactionary, aiming to replenish dopamine levels after dopamine-producing neurons in the brain have died. Without a more detailed understanding of the behavior of dopamine-producing neurons, it has been impossible to develop treatments that would prevent the destruction of these neurons in Parkinson’s patients.
Recent research provides insight into the inner workings of dopamine-producing neurons, and may lead to a new drug treatment that would proactively protect the neurons from decay. By examining the alpha-synuclein protein in yeast cells, scientists have determined that toxic levels of the protein have a detrimental effect on protein transfer within the cell. More specifically, high levels of alpha-synuclein disrupt the flow of proteins from the endoplasmic reticulum, the site of protein production in the cell, to the Golgi apparatus, the component of the cell that modifies and sorts the proteins before sending them to their final destinations within the cell. When the smooth transfer of proteins from the endoplasmic reticulum to the Golgi apparatus is interrupted, the cell dies.
With this in mind, researchers conducted a genetic screen in yeast cells in order to identify any gene that works to reverse the toxic levels of alpha-synuclein in the cell. Researchers discovered that such a gene does in fact exist, and have located the genetic counterpart in mammalian nerve cells, or neurons. This discovery has led to new hopes that drug therapy could potentially activate this gene, thereby suppressing the toxicity of alpha-synuclein in dopamine-producing neurons.
While drug therapy to suppress alpha-synuclein has been examined in yeast, fruitflies, roundworms, and cultures of rat neurons, researchers are hesitant to conclude that such therapies will prove successful on human patients. Alpha-synuclein toxicity seems to be one cause for the death of dopamine-producing neurons in Parkinson’s patients, but other causes may exist. Most scientists involved with Parkinson’s research do agree, however, that such promising early results provide a basis for further testing.

One function of the third paragraph of the passage is to

A highlight the many similarities between yeast cells and mammalian nerve cells

B explain in detail the methods used to conduct a genetic screen in yeast cells

C further explain the roles of various cellular components of yeast cells

D identify the genes in yeast cells and mammalian nerve cells that work to reverse the toxic levels of alpha-synuclein

E clarify the relevance of genetic testing in yeast cells to the search for a new treatment for Parkinson’s disease

Can you pleaseexplain why D is incorrect ?
As per my understanding 3rd para did identify the existence of the gene to counter to toxicity.