Which statement best describes Germany's submarine campaign during World War I?

Germany made no use of submarines.

Germany used submarines in land and sea attacks.

German submarines made unrestricted attacks on ships.

German submarines prevented all transatlantic shipping.

Answer: German submarines made unrestricted attacks on ships.

Explanation: According to the policy of unrestricted submarine warfare, which was first introduced during the First World War, Germany declared the entire area around the British Isles a war zone. According to this decision, all ships will be attacked by German submarines, whether military or commercial ships. It did not matter if they were allies or ships of neutral states. Thus, among others, the British passenger ship Lusitania was attacked and sunk, which also contained American travelers.

Germans waged unrestricted submarine warfare, and one of the many last straws was the sinking of the Lusitania.