What role did U-boats play in WWI and how did the Allies respond?

• A. German submarines hunted Allied shipping; the response included convoy systems, depth charges, and improved antisubmarine warfare.
• B. They blockaded the Atlantic; the Allies responded with air raids.
• C. They engaged in surface battles with battleships; the Allies built larger fleets.
• D. They supported land invasions via coastal bombardment.

Answer: (A)

U-boats disrupted Allied shipping across the Atlantic, sinking merchant ships to starve Britain of supplies and threaten the war economy. The Allied response focused on protecting what remained by using convoys—groups of merchant ships sailing together under the protection of warships and patrol aircraft—so it was harder for submarines to work unseen and to overwhelm defenses. When a submarine was detected, depth charges and other anti-submarine measures were used, and overall improvements in escort coordination, patrols, and air cover helped reduce losses. This combination of organized convoy protection and stronger anti-submarine warfare gradually kept the sea lanes open and undermined the U-boat threat.