What limitation did the U.S. impose on Soviet naval vessels during the Cuban Missile Crisis?

During the Cuban Missile Crisis, the United States implemented a naval quarantine, which effectively restricted the movement of Soviet naval vessels in the vicinity of Cuba. This was a pivotal action, as the U.S. sought to prevent the deployment of additional Soviet military equipment, particularly nuclear weapons, to the island. By prohibiting any Soviet naval ship from approaching Cuba, the U.S. aimed to assert control and send a clear signal of its stance against the Soviet Union's military buildup in the region.

The action taken was part of a broader strategy to ensure national security while avoiding direct military confrontation. This quarantine was not just a simple blockade; it involved heightened vigilance and the use of U.S. Navy ships to monitor and intercept Soviet vessels, ensuring that no arms or military supplies could reach Cuba.

The other options presented do not accurately reflect the specific limitations imposed during this crisis. While there were various maritime regulations and inspections in place, the key point was the prohibition on Soviet naval movements close to Cuba, which played a critical role in the tense standoff between the two superpowers at that time.