Is there a way to protect an online form used to populate a SmartSheet?

I have a form that I use to gather data. I send the user the form, the user enters the data and clicks Complete and the data is then added as a new row in my SmartSheet. The questions in the form are very confidential and I don't want someone inadvertently gaining access to it. Is there a way to protect who can open that form link? Or to password protect it?

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