option for dealing with multiple subtitles

subtitle-choice.txt

{
  "@context": "http://iiif.io/api/presentation/3/context.json",
  "id": "https://preview.iiif.io/cookbook/0219-using-caption-file/recipe/0219-using-caption-file/manifest.json",
  "type": "Manifest",
  "label": {
    "en": [
      "Lunchroom Manners"
    ]
  },
  "items": [
    {
      "id": "https://preview.iiif.io/cookbook/0219-using-caption-file/recipe/0219-using-caption-file/canvas",
      "type": "Canvas",
      "height": 360,
      "width": 480,
      "duration": 572.034,
      "items": [
        {
          "id": "https://preview.iiif.io/cookbook/0219-using-caption-file/recipe/0219-using-caption-file/canvas/page",
          "type": "AnnotationPage",
          "items": [
            {
              "id": "https://preview.iiif.io/cookbook/0219-using-caption-file/recipe/0219-using-caption-file/canvas/page/annotation",
              "type": "Annotation",
              "motivation": "painting",
              "body": [
                {
                  "id": "https://fixtures.iiif.io/video/indiana/lunchroom_manners/high/lunchroom_manners_1024kb.mp4",
                  "type": "Video",
                  "height": 360,
                  "width": 480,
                  "duration": 572.034,
                  "format": "video/mp4"
                },
                {
                  "type": "Choice",
                  "items": [
                    {
                      "id":"https://fixtures.iiif.io/video/indiana/lunchroom_manners/lunchroom_manners.vtt",
                      "type": "Text",
                      "format": "text/vtt",
                      "label": {
                        "en": [
                          "Captions in WebVTT format"
                        ]
                      },
                      "language": "en"
                    },
                    {
                      "id":"https://fixtures.iiif.io/video/indiana/lunchroom_manners/lunchroom_manners_fr.vtt",
                      "type": "Text",
                      "format": "text/vtt",
                      "label": {
                        "fr": [
                          "Légendes au format WebVTT"
                        ]
                      },
                      "language": "fr"
                    }
                  ]  
                }
              ],
              "target": "https://preview.iiif.io/cookbook/0219-using-caption-file/recipe/0219-using-caption-file/canvas"
            }
          ]
        }
      ]
    }
  ]
}