Google Apps Script API
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    A DataValidation for a GridItem.

    // Add a grid item to a form and require one response per column.
    var gridItem = form.addGridItem();
    gridItem.setTitle('Rate your interests')
      .setRows(['Cars', 'Computers', 'Celebrities'])
      .setColumns(['Boring', 'So-so', 'Interesting']);
    var gridValidation = FormApp.createGridValidation()
      .setHelpText(“Select one item per column.”)
      .requireLimitOneResponsePerColumn()
      .build();
    gridItem.setValidation(gridValidation);