1. Add a question in the Form using the Dropdown menu. Enter the list of reviewers email addresses
2. Tick Pick reviewer email from your Form in the Conditional validation step. Set the criteria, and choose the column in your spreadsheet containing email address(es).
Note that it is not possible to tick the box Pick reviewer email from your Form at the default step. If you don't want to add any conditions inside the step then choose a condition that will be met every time.
For example, First name >> Not equal to >> gibberish or Email address >> Contains >> @
3. Share your spreadsheet with the email addresses entered in the Form in Step 1.