27. Machine learning can be divided into supervised learning and unsupervised learning. The two problems most commonly dealt with in supervised learning are regression and classification. When you predict the target to be a continuous numerical value, we call it regression； if the target is discrete, we call it classification. Which one of the following common algorithms is NOT a classification algorithm? (A) SVM (B) Linear (C) Decision trees (D) KNN (E) Naive Bayes