How can i set randomization of options in a groups?
Example:

Q. Which brands are you using/ used?

1. A

 2. B

 3. C

4.D

5.E

6.F

7.None

Here, I want to randomize option 1-6 in two groups. Group-1, option-1 to option-3 and Group-2, option-4 to option-6 and options will randomize within groups.