$($a$)$ Use the Machine Learning algorithms k$-$NN$,$ Logistic regression, and Linear Discriminant Analysis to classify between patients with Parkinson's and healthy control subjects, using the database DB$\_$Voice$\_$Features.csv and evaluate the performance.

$($b$)$ Apply parameters optimization to $($a$)$ and evaluate the performance.

$($c$)$ Explain the Confusion Matrix obtained in $($a$)$ y $($b$),$ that is$,$ before and after parameters optimization.