json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "title": "MultipleChoice question options",
      "description": "Options for a MultipleChoice question.",
      "type": "object",
      "additionalProperties": false,
      "required": [
          "text",
          "correctAnswers",
          "incorrectAnswers"
      ],
      "properties": {
          "text": {
              "description": "The question HTML text that comes before the options.",
              "type": "string"
          },
          "correctAnswers": {
              "description": "A list of correct answers to the question. Each is an HTML string.",
              "type": "array",
              "items": {
                  "type": "string"
              }
          },
          "incorrectAnswers": {
              "description": "A list of incorrect answers to the question. Each is an HTML string.",
              "type": "array",
              "items": {
                  "type": "string"
              }
          },
          "numberAnswers": {
              "description": "The total number of answers in the list of possible answers.",
              "type": "integer",
              "minimum": 1
          },
          "minCorrectAnswers": {
              "description": "The minimum number of correct answers in the list of possible answers.",
              "type": "integer",
              "minimum": 0
          },
          "maxCorrectAnswers": {
              "description": "The maximum number of correct answers in the list of possible answers.",
              "type": "integer",
              "minimum": 0
          }
      }
  }