What does specifying feature$\_$names$\_$out$=$"one$-$to$-$one" in a FunctionTransformer imply about the output features? Check all that apply.

a$)$ Each output feature is a combination of all input features.

b$)$ The output features are named differently from the input features.

c$)$ Each output feature corresponds directly to an input feature.

d$)$ New features are created with generic names based on the operation performed and the original feature names.