In a medium bowl, combine corn, olives, red pepper and onion.
In a small mixing bowl, stir together olive oil, lemon juice, apple cider vinegar, oregano, salt, pepper and garlic. Pour over corn mixture; toss to coat. Cover, and refrigerate at least 4 hours or overnight.
Just before serving, peel, pit and chop avocados. Stir into salsa. Serve with tortilla chips.
Note: Extended refrigeration needed for this recipe. Nutritional information does not include tortilla chips.