What does a Java "class" file contain?

A Java "class" file contains bytecode, which is a set of instructions that the Java Virtual Machine (JVM) can execute. When a Java program is compiled, the Java compiler translates the source code (written in .java files) into bytecode, which is stored in .class files. This bytecode is platform-independent, allowing it to be executed on any platform that has a compatible JVM.

The other options do not apply to what a class file contains: Java class files do not include images or multimedia resources, as those are handled separately. They also do not consist solely of documentation for developers; instead, documentation plays a different role in software development and does not form part of the executable code. Finally, class files are not data files for storage; they specifically hold the compiled instructions for the program to run effectively on the virtual machine. Therefore, the emphasis on the Java Virtual Machine's dependency on class files for executing bytecode makes the first option the correct answer.