Refer to the input text as context and select the correct relationship between 'Vittorio Colao' and 'Vodafone' from the available options.
Options: developer, platform, operator, employer

LONDON, July 21 (Reuters) - Vodafone said the bosses of its four biggest European markets would report directly to chief Vittorio Colao to speed up decision making in fast-changing markets, after it decided to scrap its European regional management structure.
employer