Final answer:
Diagnosing Alzheimer's and Parkinson's is challenging due to the lack of effective diagnostic tools and the overlap in symptoms with normal aging, as well as the variability of symptoms among patients.
Step-by-step explanation:
It is difficult to diagnose Alzheimer's disease and Parkinson's disease because of both lack of effective diagnostic tools (A) and similarities in symptoms (B). The symptoms of these diseases can be similar to those experienced during normal aging, such as memory loss, confusion, and changes in movement or smell, making it challenging to distinguish between normal aging and disease. Moreover, the diagnostic tools we currently have may not be effective enough to detect these diseases early on; the development of new techniques such as brain imaging with Pittsburgh Compound B and searching for biomarkers are still in progress. Additionally, the symptoms display variation among patients, and the underlying genetic and environmental factors are not fully understood.
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