"Best" depends on the goals.
Blockchain provides "finality" through a data structure and a process that makes it possible to reason about finality. That is a deliberately vague description because there are many variations on the structure, the process and the idea of confirmation.
BFT uses validators. They are privileged and they could (...
The oracle problem is:
"Corrupt data imported on-chain causes catastrophes for auto-executing smart contracts"
That's really it. Once data is reported to a blockchain, that data is now an immutable part of the history of the blockchain. If a smart contract executes incorrectly based off that data, your contract is not only not doing what it was ...
Check out these papers. They may help you!
Look at the Appendix of this one;