I understand your difficult to express yourself in english while it's not your main language. By understanding it I can feel what you mean and I'll try my bet.
You don't need an array for it, just a global variable is sufficient.
While you create an object on the screen, it have something called Instance Variable on the left side of the screen. By default it's empty, but you can change it by adding a Boolean variable, for example, called Type. Set the default to be "false".
I don't know if you're creating your buttons on the screen or they are permanent, so, I'll assume the first, you're creating your buttons on the screen while the game is running.
While creating your buttons on the screen, you may use the follow event sequence;
Question start:
Action: Create Sprite Button 1 at X1,Y1;
Create Button 2 at X2,Y2;
etc;
Now, you'll change it to:
Create Sprite Button 1 at X1,Y1;
Set Sprite Button "boolean" variable to "true" (or "false" depending of your wish);
Create Sprite Button 2 at X2,Y2;
Set Sprite Button "boolean" variable to "true" (or "false" depending of your wish);
They are in sequence, so, you'll be able to know what button have the true answer and will be able to check if the player has pressed it, adding points to his score.
To check it is simple:
Conditions: Click or Touch on the object AND Object Boolean Variable is true;
Action: Add 10 to the Score Global Variable;
Condition: Else
Action: Subtract 10 points (or do nothing, depending of your wish)