What does the Java Development Toolkit (JDK) provide for developers?

The Java Development Toolkit (JDK) is an essential software development kit for Java developers. It provides a comprehensive set of tools that are necessary for developing and running Java applications. This includes the Java compiler (javac), which translates Java source code into bytecode, the Java Runtime Environment (JRE) that allows for executing Java programs, and other utilities like the Java debugger and Java documentation generator.

These tools work together to facilitate everything from writing code to managing application performance and debugging during development. Therefore, option A accurately summarizes the primary function of the JDK, as it encapsulates both the tools needed for program development and the required components to run these programs effectively on a machine.

The other choices represent areas that are not core functions of the JDK. For instance, while a library for database management might be part of a larger Java application ecosystem, it is not a directly provided tool of the JDK. Similarly, a web framework or a graphical user interface designer may exist as separate libraries or frameworks that can be used alongside Java development, but they are not included in the JDK itself.