text: {"answer": "back to back", "query": "Are the trucks parked front-to-back or back-to-back?", "question_id": 499835000, "contrast_sets": [{"mutex_answer": "front to back", "mutex_caption": "Two delivery trucks are parked front to back."}], "caption": "Two delivery trucks are parked back to back.", "image_id": 499835, "id": 18, "file_name": "COCO_val2014_000000499835.jpg", "coco_url": "http://images.cocodataset.org/val2014/COCO_val2014_000000499835.jpg", "flickr_url": "http://farm9.staticflickr.com/8500/8310420221_1e5af98fd5_z.jpg", "license": 4, "height": 480, "width": 640}