Which of the following statements are true?

I. Every left-recursive grammar can be converted to a right-recursive grammar and vice-versa II. All $\epsilon$ productions can be removed from any context-free grammar by suitable transformations III. The language generated by a context-free grammar all of whose productions are of the form X --> w or X --> wY (where, w is a string of terminals and Y is a non-terminal), is always regular IV. The derivation trees of strings generated by a context-free grammar in Chomsky Normal Form are always binary trees