Unrestricted submarine warfare, which became prominent in World War I, meant that submarines could sink any time of vessel at any time without warning. Before this, they had to surface first and place crews on lifeboats.
The answer should be the right to personal property since the Ninth Amendment protects rights that aren't mentioned in the Constitution. (speech and religion are in the 1st Amendment, and right to a fair jury is the Sixth Amendment)
Hope this helps!
