The answer is: A. collecting data
During this process , researchers would use their observational skills and record every notable occurrence that happen to the variables.
The focus on this process is simply to add all relevant data without making any analyzation. That process come later on after the researchers started to change the variables in order to see whether it would create a correlation.
Parkinson’s disease is triggered by degeneration of dopamine-producing neurons in the brain. <span> <span><span> <span> Parkinson's disease is a neurodegenerative disease of the CNS resulting from degeneration of dopamine-producing neurons in a region of the midbrain called the substantia nigra. Some of the factors that induce this disease are oxidative stress<span>, inflammation, and dysfunctional mitochondria. The disease is progressive including characteristic symptoms such as tremors, muscle rigidity, loss of coordination bradykinesia (slowness and difficulty with movements), sleep disturbances...</span> </span> </span> </span></span>
I think the best answer would be white blood cells
Given the answers;
a) Reptiles
b) Cactus plants
c) Small birds
d) Crabs and crayfish
The answer is C. Small birds.
On his visit to the Galapagos Islands, Charles Darwin discovered several species of finches that varied from island to Island, which helped him to develop his theory of natural selection.
Answer:
the correct answer is a
ARE BASED ON A SET OF OBSERVATIONS
hope this helps!