You've just finished training a decision tree for spam classification, and it is getting abnormally bad performance on both your training and test sets. You know that your implementation has no bugs, so what could be causing the problem?

A. training based on historical data B. prediction to answer a query C. both A and B D. automization of complex tasks

A. scalable B. accuracy C. fast D. all of the above

A. machine learning model B. machine learning algorithm C. null D. accuracy

A. data mining. B. artificial intelligence C. big data computing D. internet of things