You can use an instance variable "Correct" on each word object, and set it as true or false.
1. Draw a random word to display, set variable "Correct" to true.
2. Draw 4 more words to display, set variable "Correct" to false.
3. On clicked word object, compare instance variable "Correct" is true or false, and increment the relevant counter.
You probably want an array to represent your deck, but you might be able to do it with the advanced random plugin and a dictionary instead.
Don't be afraid of learning arrays as a concept. An array is basically just a spreadsheet, where each cell is a variable. In other words, its a group of variables you can identify by coordinate position rather than names.