Attempt the question, check the explanation, and continue with similar questions to build confidence before exams.
{(red, circle), (blue, circle)}
{(red, blue)}
{(red, square), (blue, square), (blue, circle), (red, circle)}
{(red, circle), (red, square), (blue, circle), (blue, square)}
Continue with nearby questions to strengthen the same chapter concept while you still have the context fresh in mind.