what kind of policies ensure that there is a level playing field for labour,managers,shareholders in MNCs?

Answer 1

There is no way to ensure it. The world is not a level playing field, and MNCs take full advantage of this fact. They move labor-intensive segments of their business to low-wage locations, capital-intensive segments to locations with good property rights enforcement and low property taxes (have you ever wondered how oil refineries end up in places like Barbados and Singapore?), and arrange financing in the markets where it is currently cheaper.