Which is a valid meaning of trigger?

• A. to bring about
• B. to cause
• C. to set something off
• D. to make something happen

Answer: (C)

Trigger means to start or activate something, often causing a reaction or sequence of events. That sense fits best with the idea of setting something off—when a trigger activates a mechanism or begins a reaction, you say it sets off the event. So, using it to describe starting an alarm, a chain of events, or a reaction is natural: a spark can trigger a fire, a reminder can trigger a memory, or an action can trigger a response. The other options are related ideas—causing or bringing about something or making it happen—but they’re more general and don’t emphasize the initiating, activating sense that trigger carries.