PCA reduces dimensionality by transforming features into principal components, improving classification performance by reducing noise and overfitting.
Here is the code snippet you can refer to:

In the above code we are using the following key points:
- Uses PCA to reduce feature space from four dimensions to two.
- Reduces noise and simplifies model training while retaining key variance.
- Evaluates performance after dimensionality reduction.
Hence, applying PCA improves classification efficiency by reducing dimensionality, minimizing overfitting, and speeding up model training without significant loss of information.