"Looking at trying to integrate xAPI storyline into Moodle.
We want the answers to the questions that students submits."
You'll need the Moodle xAPI launch plugin and an LRS. There's a video showing the plugin working with Watershed LRS here: https://www.youtube.com/watch?v=qJxO4Ene2kM
You might also like to take a look at SCORM Cloud LRS.
Does that help?