下列各种Java类的定义,那些是错误的?( ) A. class MyClass{ private int Val; public int getVal(){ return Val; } } B. class MyClass1{ private static int Val; public int getVal(){ return val; } } C. class MyClass2{ private int Val; public static int getVal(){ return Val; } } D. class MyClass3{ private static int Val; public static int getVal(){ return Val; } }