Given the following data samples $($square and triangle belong to two different classes$),$ which one$($s$)$ of the tollowing a'gerthins ming produce zero training error? $($You can choose multiple answers$)$

$3.$ KNN with $k=1$

b$.KNN$ with $k=19$

a$.$ C$.$ Linear Logistic Regression

a d Logistic Regression with polynomial transformation