Image Opacity = 0 But Appear for a Sec on Preview

Questions
1

In this activity, students can pick one food to see the nutrition facts of the food.
I upload the nutrition facts as images in the GRAPH, and set the opacity of each to 0. So when the students pick one food (from the multiple choice), the opacity will turn to 1 (Slide 1).

On the preview, the images are still appear (even though just for a second).
BUT, when I only upload the image and set the opacity to 0, without CL connecting GRAPH and Multiple Choice, there images are clearly disappear (Slide 2).

Should I change the CL? How so?
Thank you in advance.

Image Opacity = 0 But Appear for a Sec on Preview

2

Hello,
Right now I don’t see either of the screens in your activity. You may have to publish your current draft.
I don’t think you need to change your CL; I expect (but am not 100% sure) that this is a small glitch in the Preview feature that will not happen when students join the activity. You can always run a test session of your activity and join it as a student to see if the images still show up.