Detailed Explanation:

Answer: Option 2 — World Bank collaboration that facilitates the preparation and structuring of complex infrastructure Public-Private Partnerships PPPs to enable mobilization of the private sector and institutional investor capital.

The Global Infrastructure Facility (GIF) is a partnership led by the World Bank Group that brings together governments, multilateral development banks, private sector investors, and financiers to design and structure bankable infrastructure projects. It specifically focuses on facilitating complex infrastructure Public-Private Partnerships (PPPs) in emerging markets and developing economies to mobilize private sector and institutional investor capital. The GIF provides technical advisory support and works to ensure that infrastructure projects are properly structured to attract private investment, making Option 2 the correct answer.