Which of the following selects the best K high-score features.

The correct answer is D. all above.

• Selectpercentile selects the top K features with the highest percentile scores.
• Featurehasher converts features into a set of hash codes, and then selects the top K features with the highest hash code frequencies.
• Selectkbest selects the top K features with the highest scores, where the scores are calculated using a variety of methods, such as chi-squared, mutual information, and information gain.

All of these methods can be used to select the best K high-score features. The choice of method will depend on the specific application. For example, if the features are categorical, then selectpercentile may be a good choice. If the features are continuous, then featurehasher or selectkbest may be a better choice.