Use the Feynman technique, or more simply, you'll know you understand what you did wrong when you're able to explain the problem and answer to a child. If you can't explain it - there are gaps in your understanding that you need to revisit.

The most important part of the studying process is making sure you understand why an answer is correct and why the incorrect answers are not. Review, review, review. Use the video explanations, the correct answer explanations, and copy and paste the question to view other online forums to understand the logic behind the correct answer.

In each review session, you'll learn to spot the patterns. Perhaps the wrong answer you selected didn't explicitly use vocabulary from the prompt, perhaps the incorrect answers make assumptions outside the scope of the stimuli, etc. The more problems you do, and the more in-depth review, the more you'll see that the questions are fairly similar in how they try to trip you up and what they're looking for in a correct answer.

Review to understand, review well, and practice explaining the question and answer as if you were a teacher.