Nuveen Real Estate Securities Select Fund A 

This fund primarily concentrates its investments by allocating a minimum of 80% of its total assets to companies deeply involved in or connected with the property sector, encompassing those that possess substantial real estate holdings. Furthermore, it has the discretion to commit up to 15% of its capital to real estate-focused securities from international entities. The portfolio also allows for diversification, with up to 20% of its value potentially invested in stocks and bonds issued by companies that operate outside the real estate industry.