Answer
Darryl cannot cross the sea by water, since that was how fishes do. This render every boats and water transportation unqualified.
He can neither fly by air, because that was how birds do. Therefore, helicopters and jet planes would do him no good at all.
There was only one way to cross the par line then— by a bridge.
Neither the fish, not the birds uses a bridge to cross the par line, do they?
Darryl knew the answer the moment the Cheiftana gave him the question. He knew that the Cheiftana was playing tricks on him but there was one thing she could have missed, the Manggan Island was behind when it comes to technology and infrastructure. She must have never thought that bridges can be built to connect a tiny island to another even they were ocean's apart.(If you are reading this novel outside webnovel.com site, it means it had been stolen. To get full and updated version please visit https://www.webnovel.com/book/10355083706015805/The-Genius'-First-Love )