Ok here is my design

I have designed everything fine

My idea goes like this....

I am going to create a master table which is going to store all the questions, the fields of the table might be like this...
Qno question option1 option2 option3 option4 answer
Now I will allow the administrator to select the required number of questions say 20
I will save these 20 questions in another table temporarily until the exam date and I will retrieve these 20 questions randomly for each student,
These 20 questions will be deleted automatically 1 day after the exam

Now I got a new problem suppose if there r questions like ...say giving a paragraph and asking 5 questions related to that question.
These type of questions cannot be randomized

How can I modify my database design in order to store and retrive above type of questions

Please help me......
Waiting for ur help...