Maria's advice is correct. However, I wouldn't use the free option because it allows you too much wiggle room because the object bounding box is wider than the optimal target area.
- I offer a suggestion on how to rework the clip images so you have more control over where to drop the object target.
- The red clip has a selected state but doesn't look different that's why you don't see the state change. Also, selected isn't the appropriate state for this activity because it's a toggle and the user can turn it off and on without moving the object. I'd use a drop correct state.
I recorded a video that explains this and how I'd recommend making adjustments to your activity. Hope it helps.
https://360.articulate.com/review/content/b2e70935-3926-4d28-91a3-cc4438c8c15e/review