The answer is D.
Heres why:
A Pure rubbish Dopamine production is not the cause of any issue.. it is the last product marker in chain of events prior. It is the effect.. of dying cells, not the cause of the problem.
B. This is a step too far, the Gene is NOT missing or not functioning well. We dont know that for sure.
c. Nonsense. drug therapy has proven effects in yeast cells. Something is happening with manipulation.
d. YES of course
E. NO alpha-synuclein is not a toxic product, it is however at HIGHER CONCENTRATIONS implicated with toxic effects.
The answer is D.
