What was the name of the 2016 attack conducted by an individual pledging allegiance to ISIS?

The Orlando nightclub shooting, which occurred on June 12, 2016, is correctly identified as the attack conducted by an individual who pledged allegiance to ISIS. This attack took place at the Pulse nightclub in Orlando, Florida, and resulted in 49 fatalities, making it one of the deadliest mass shootings in U.S. history at that time.

The gunman, Omar Mateen, called 911 during the event and expressed his allegiance to ISIS, which is crucial in understanding the attack's context as a directed act of terrorism inspired by a larger extremist ideology. This incident underscored the ongoing threat posed by ISIS sympathizers and highlighted the need for vigilance and counterterrorism measures in preventing similar attacks.

By contrast, the Boston Marathon bombing and the Chattanooga attacks, while also significant, were not directly tied to ISIS pledges at the time they occurred. The NAVSEA shooting, which refers to a 2019 incident, does not fit the 2016 timeframe or the context of ISIS involvement. Therefore, the Orlando nightclub shooting stands out as the singular event in this specific context.