All or any part of the proceeds of the bonds may be contributed or paid to any agency, board, commission or entity constituted or provided for by agreement under or pursuant to Article 1, Chapter 5, Division 7, Title 1 of the Government Code, if the board of supervisors shall find that such contribution will effectuate a purpose stated in the bond proposition and will be in aid of a purpose which will materially benefit and serve the general county interest and that the public interest, convenience, and neccessity of the county as a whole requires the contribution to be made by the county.