If you have a library containing a set of classes there are many reasons for which you will prefer to extend it without changing the code that was already written (backward compatibility, regression testing). This is why we have to make sure our modules follow the ... .

What is mean by “Module” and “Reason to change” in explanation?

This class satisfies the 'Single responsibility principle'?

SOLID are five basic principles that help to create good software architecture. SOLID is an acronym where:-

Please choose what tools can be used to allow access to the common resources for the one thread.

Object of what class should be used to allow access to common resources for the setted amount of threads only? 

What delegate should be used to create thread that can be started with some parameters?

Please choose the correct ways to create new thread myThread that executes Calculation() method:

What is the default priority of the thread?

Please choose the methods that can be used to block the thread