Underestimating people is a huge mistake. Often, those who appear to be innocent are everything but.
To whom it may concern, In regards to the Memorial Day Fiasco aboard your cruise ship, star princess we would first offer our sincere apology, for our part in the mishap. While we do not plan on taking legal action against you or the Maroccan authorities, we are requesting parties to avoid another Waterloo captain. Johnson may just want to remember a key items.
I would say that the example of satire among these options is d. Those two old brothers had been having a pretty hot argument a couple of days before, and had ended by agreeing to decide it by a bet, which is the English way of settling everything.
Twain is criticizing and mocking the English for settling everything in such a trivial manner as betting.