Which AI tool is the most accurate for solving university exams? ChatGPT vs Gemini vs Perplexity

I’m currently studying for a university exam and want to test which AI tool is the most accurate for exam-style questions (Multiple Choice). I have several past exams and plan to solve them using AI.

So far, ChatGPT is my first choice, but I keep seeing Gemini and Perplexity mentioned as strong alternatives.

From your experience:

Which tool gives the most accurate answers for university-level problems?

Which one is also reasonably fast and reliable?

Any insights or comparisons would be greatly appreciated.

Thanks!