Good Riddles

Question: Sophie who is a housemaid, knows her boundaries well. She is good at equations. Her favorite vegetable is cauliflower. Which is her favorite plant?

Question: What speaks with its ear, listens with its mouth, and has 10 digits but no hands?

Question: What goes black when you buy it, red when you use it, and goes white when you throw it away?

Question: You use me. I keep you neat. Every once in a while you empty me out. What am i?

Question: A traveler is walking in the jungle. Then he found 4 paths. In the first one has a really deep mud. When people go there, they never come back. Second path have broken tracks, which is really unsafe for the people who take this path. In the third path, there is lion who didn't eat and drink anything for 3 months, so it might be really hungry by now. Last one have dinosaurs and volcanoes, so it's a very dangerous place. So, which path is the best for the traveler to take.