In a simple case the general score could just be the sum of the scores.
You can further tweak that to give some scores priority over others like:
which would give the "a" score the highest priority.
It can be more finely adjusted to adjust the priorities of the scores. You could even pick the factors at random to get a unique ai.
I suppose you could use any arbitrary formula to combine the scores into one value as well, but probably simpler is better.