在咳嗽或打喷嚏时用纸巾盖住口鼻、接触呼吸道分浸物后实施手卫生,并与其他人保持（）以上距离的一组措施

A、Both of them are methods to deal with overfitting problem
B、Pre-pruning does not split a node if this would result in the goodness measure falling below a threshold
C、Post-pruning removes branches from a “fully grown” tree
D、It is easy to choose an appropriate threshold when making pre-pruning