"which one" meaning in Anglais

{
  "categories": [
    {
      "kind": "other",
      "name": "Compositions en anglais",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Pronoms interrogatifs en anglais",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Anglais",
      "orig": "anglais",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "Composé de which et de one."
  ],
  "lang": "Anglais",
  "lang_code": "en",
  "pos": "pron",
  "pos_title": "Pronom interrogatif",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Exemples en anglais",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              0,
              9
            ]
          ],
          "text": "Which one of these cakes do you prefer?",
          "translation": "Lequel de ces gâteaux préferes-tu ?"
        }
      ],
      "glosses": [
        "Lequel, laquelle."
      ],
      "id": "fr-which_one-en-pron-CbUeZkDl"
    }
  ],
  "sounds": [
    {
      "ipa": "\\ˈwɪtʃ wʌn\\"
    }
  ],
  "synonyms": [
    {
      "word": "which"
    }
  ],
  "tags": [
    "interrogative"
  ],
  "word": "which one"
}

{
  "categories": [
    "Compositions en anglais",
    "Pronoms interrogatifs en anglais",
    "anglais"
  ],
  "etymology_texts": [
    "Composé de which et de one."
  ],
  "lang": "Anglais",
  "lang_code": "en",
  "pos": "pron",
  "pos_title": "Pronom interrogatif",
  "senses": [
    {
      "categories": [
        "Exemples en anglais"
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              0,
              9
            ]
          ],
          "text": "Which one of these cakes do you prefer?",
          "translation": "Lequel de ces gâteaux préferes-tu ?"
        }
      ],
      "glosses": [
        "Lequel, laquelle."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\ˈwɪtʃ wʌn\\"
    }
  ],
  "synonyms": [
    {
      "word": "which"
    }
  ],
  "tags": [
    "interrogative"
  ],
  "word": "which one"
}