How to check which gameobject was clicked in Vuforia?

I'm making a project for one of my classes using Vuforia. In short, there are 3 target images and each image spawns 3 cubes with different symbols on them. One person knows the correct symbol and must verbally describe it to the other player. Player clicks on 3 correct symbols, they win. 3 incorrect guesses, game over.
I have set up to where each set of symbols will randomly select the correct symbol of that set, set up the scene transitions, animations, etc. The hurdle I'm struggling with is how to check what game object was clicked to add to either the correct guess counter or the incorrect guess counter and then change that cube's color to signify to the player if it was a correct or incorrect guess.
How would I do what is essentially:
private void OnMouseDown(){
if(objectClicked == CorrectSymbol){
correctGuess++;
objectColor = green;
}else{
wrongGuess++;
objectColor = red;
}