Right, lemme see, So three pages: home page, login/register, and survey. Tests that you can route users post-login appropriately depending on their history with the survey. Design requirements, if any, not provided, so don't know how complicated the frontend is; but sounds reasonable so far...
So what is the question that gets asked?
"How to integrate React with Ruby-on-Rails"
And the answer?
Create a Ruby-on-Rails API and a dedicated frontend in React.