I think I had better maintain some distance from you when giving the answer, else I might get hurt. Can you believe it .... none of the children could make ONLY THREE CORRECT guesses! Out of the 50 children, 32 got their guesses all wrong, eight could guess only one sweet correctly while six children had two guesses right. That leaves FOUR CHILDREN AND ALL THE FOUR OF THEM CORRECTLY GUESSED ALL THE SWEETS!
How is it possible for someone to guess three sweets correctly and get the fourth one wrong? Suppose you had been one of the participants and you had correctly guessed that Cup No. 1 covered "laddoo", Cup No. 2 covered "pedha" and Cup No. 3 covered "gulab jamoon". Therefore, Cup No. 4 had to cover "barfi". How can you get that wrong?