After discovering what they thought was a threat in Cuba, Kennedy's team debated whether to

The best and most correct answer is After discovering what they thought was a threat in Cuba, Kennedy’s team debated whether to "establish a naval blockade or create a hotline." This was part of the major sequence of events during the Cuban Missile Crisis.

They were deciding whether to create a naval blockade, because the Cubans were traveling mostly by ocean, or they wanted to do a military strike. They could not decide of which would have been the most efficient way to attack the Cubans.