If you have been set a knowledge quiz, this will appear in your 'My tasks' list:
Clicking on your knowledge quiz will take you to that quiz, you can then select 'Start':
In the knowledge quiz window you will be able to see how many questions are in the quiz, and how many marks a question is worth, you can easily move between questions. (You can exit the quiz at any time and your answers will be saved.)
Once you have answered all the questions you can click 'Finish':
Your quiz results will then appear. You have the option to review any answers submitted:
When reviewing answers you can chose to see the correct answer:
You will also be able to see any knowledge quiz results in your reports.