I consider these four composers the most important to come out of Latin America.
Well now. That seems to open things up to asking you some personal questions, two pertinent ones being "How many Latin American composers are you familiar with?" and "Why? Why do you consider these four the most important?"
There are also ones like "What do you mean by 'important'?," but perhaps the first two are enough for now?
Otherwise, I have two names for y'all, one a recently deceased composer, Mauricio Kagel, one a still living composer, Julio Estrada. (There are more, of course, but these two have really pushed the boundaries of music in a very real, very legally binding way.*)
*This last bit is a Python reference, and not a point for argument. Unless you're just doing it in your spare time.**
**Yes, it is.