Which of the following is NOT a tactic used by terrorist groups?

Public speaking events do not typically serve as a tactic used by terrorist groups. Instead, terrorist tactics are generally aimed at instilling fear, creating chaos, and exerting pressure on a target or government to achieve specific ideological or political objectives.

Tactics such as bombings, cyber attacks, and hostage-taking are directly designed to create immediate threats or leverage over the public or authorities. Bombings cause destruction and loss of life, cyber attacks can disrupt critical systems or steal sensitive information, and hostage-taking creates a situation where individuals are held to exert influence or demand concessions.

In contrast, public speaking events are generally peaceful gatherings intended for dialogue, persuasion, or awareness-raising purposes, which do not align with the violent and coercive strategies typically employed by terrorist groups. Thus, this option stands out as it does not fit the modus operandi associated with terrorism.