To answer this question, you need to understand the concept of converting a class into a thread in Java.
In Java, a class can be converted to a thread by implementing the Runnable interface. The Runnable interface defines a single method named run(), which is the entry point for the thread when it is started. By implementing this interface, the class can define the code that will be executed in a separate thread when the thread is started.
Option A) Thread - This option is incorrect because the Thread class itself represents a thread, rather than converting a class into a thread.
Option B) Runnable - This option is correct because implementing the Runnable interface allows a class to be converted into a thread by defining the run() method.
Option C) Both of these - This option is incorrect because only implementing the Runnable interface is required to convert a class into a thread. The Thread class is not necessary for this conversion.
Option D) none of these - This option is incorrect because implementing the Runnable interface is the correct way to convert a class into a thread.
The correct answer is Option B) Runnable. This option is correct because implementing the Runnable interface allows a class to be converted into a thread.
Therefore, the correct answer is B) Runnable.