Which short story features children trapping a butterfly in the past, causing future chaos?

• A. A Sound of Thunder by Ray Bradbury
• B. The Time Machine by H.G. Wells
• C. All Summer in a Day by Ray Bradbury
• D. The Lottery by Shirley Jackson

Answer: (A)

The idea being tested is that a tiny action in the past can ripple forward to produce a very different future—a famous example of the butterfly effect in time travel fiction. The story that fits this concept best is the one where a hunter on a time-travel safari accidentally steps on a butterfly in the prehistoric past. That small act alters the chain of events, and when the travelers return, the present has changed in subtle and sweeping ways. The prompt mentions children trapping a butterfly, but the core moment that drives the chaos is the deliberate or accidental harm to the butterfly, not children, which is what triggers the future shifts in this tale. The other stories either don’t center on a past action causing future chaos (they explore different themes or kinds of time travel) or don’t hinge on a single small past event producing such dramatic changes.