# Collection resource properties

When a resource has a property that is a collection, this collection can also be modified. Although making a `PATCH` request allows to pass only specific properties that need to be changed, passing such a collection property in a `PATCH` request will replace the entire collection. This means that it is not possible to add/update/remove specific items in the collection.

Taking the [Form questions endpoints](../operation/operation-getformquestions) as an example, a `GET /forms/123/questions/456` response might look as follows:
```json
{
  "data": {
    "id": "456",
    "inputType": "SELECT",
    "order": 5,
    "required": true,
    "label": {
      "language": "en",
      "value": "Marital status"
    },
    ...
    "answerOptions": [
      {
        "label": {
          "language": "en",
          "value": "Single"
        },
        "value": "single",
        "externalId": null,
        "order": 0,
        "translations": {
          "label": [
            {
              "language": "en",
              "value": "Single"
            },
            {
              "language": "nl",
              "value": "Alleenstaand"
            }
          ]
        }
      },
      {
        "label": {
          "language": "en",
          "value": "Married"
        },
        "value": "married",
        "externalId": null,
        "order": 1,
        "translations": {
          "label": [
            {
              "language": "en",
              "value": "Married"
            },
            {
              "language": "nl",
              "value": "Getrouwd"
            }
          ]
        }
      }
    ]
  }
}
```

A `PATCH /forms/123/questions/456` request body to make the question optional and add an answer option should be made as follows:

```json
{
  "required": false,
  "answerOptions": [
    {
      "label": {
        "language": "en",
        "value": "Single"
      },
      "value": "single",
      "externalId": null,
      "order": 0,
      "translations": {
        "label": [
          {
            "language": "en",
            "value": "Single"
          },
          {
            "language": "nl",
            "value": "Alleenstaand"
          }
        ]
      }
    },
    {
      "label": {
        "language": "en",
        "value": "Married"
      },
      "value": "married",
      "externalId": null,
      "order": 1,
      "translations": {
        "label": [
          {
            "language": "en",
            "value": "Married"
          },
          {
            "language": "nl",
            "value": "Getrouwd"
          }
        ]
      }
    },
    {
      "label": {
        "language": "en",
        "value": "Widowed"
      },
      "value": "widowed",
      "externalId": null,
      "order": 2,
      "translations": {
        "label": [
          {
            "language": "en",
            "value": "Widowed"
          },
          {
            "language": "nl",
            "value": "Verweduwd"
          }
        ]
      }
    }
  ]
}
```

Note that even though the first two answer options remained untouched, they still need to be provided in the request because of the behavior of the `PATCH` operation on collection properties (replacement of the entire collection).