curl --request GET \
  --url https://api.hubapi.com/crm/v3/properties/{objectType} \
  --header 'Authorization: Bearer <token>'

{
  "results": [
    {
      "displayOrder": 2,
      "fieldType": "select",
      "formField": true,
      "groupName": "contactinformation",
      "hasUniqueValue": false,
      "hidden": false,
      "label": "My Contact Property",
      "modificationMetadata": {
        "archivable": true,
        "readOnlyDefinition": false,
        "readOnlyOptions": false,
        "readOnlyValue": false
      },
      "name": "my_contact_property",
      "options": [
        {
          "description": "Choice number one",
          "displayOrder": 1,
          "hidden": false,
          "label": "Option A",
          "value": "A"
        },
        {
          "description": "Choice number two",
          "displayOrder": 2,
          "hidden": false,
          "label": "Option B",
          "value": "B"
        }
      ],
      "type": "enumeration"
    }
  ]
}