# event.origin is the sender at send time, not who lives there now

Lesson 3 quiz: A, B, C, E correct; D wrong. D is “you reply with `targetOrigin` set to `event.origin`.” That string is the sender origin at send time. `targetOrigin` still checks the window *now*; if the window moved, the reply is discarded. Same “now vs then” split as LR-0004. Later lessons should keep `event.origin` (snapshot) and `targetOrigin` (check at send) as two different times.