Hi,
Below is the description of what I am trying to do:
In the test screen, the participant will be required to choose 2 pictures out of 6 by clicking them. After they click on a picture, the picture will be framed, which indicates their choice. And then they make their second choice and the second picture will also be framed. When they decide what is the two correct pictures. They need to click on the tick mark 
for moving to the test screen. On the second text screen, the pictures from the first screen will disappear except for their choices and another 6 pictures will be presented.
My questions are how to keep the pictures that the participants chose in the first screen and make them show on the next screen?
I would appreciate it if someone could help. Thank you so much.