How to retrieve information from multiple choice Forms with flow

Hello community,

I'm new to PowerBI and I'm exprecieng and issue.

I've setted up a new PowerBI dashboard from a Microsoft Forms.

In the Microsoft Forms, in some questions I've a multiple choice answer. And I would like to retrieve these informations in a chart.
In PowerBI, I've created a RealTimeData set and Microsoft Flow is used to fill this dataset.

There is the Flow :

This is the expression used : 

FIRST(triggerBody()?['value'])?['resourceData']['responseId']

But in a answer with multiple choice, I only receive that value : ["Choice1","Choice3","..."]

How could I have a chart with Choice1, Choice2, Choice3 separeted ?

Thank you in advance for your support.

Best regards,