The Traveler

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.

Question: During what month do people sleep the least?

Question: People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?

Question: When is 99 more than 100?

Question: What are the next two letters in the following series and why? WATNTLITFS__

Question: Surrounded by life , yet life is its biggest enemy. But without life there is no need for it to exist. What is it?