Professional sports teams will sometimes seek public subsidies for stadium financing projects that produce large benefits for a relatively small number of fans and impose small costs on a relatively large number of people. Sometimes these efforts to secure public funding are successful even though the decision is not efficient. This is an example of

ANSWER: THE SPECIAL-INTEREST EFFECT.

EXPLANATION: The act of seeking public funds for financing projects that produce numerous gains or benefits for a concentrated number of individuals, thereby imposing small costs on a relatively large number of individuals is referred to as SPECIAL-INTEREST EFFECT.

This proposition is often practiced by government, whereby they incorporate projects with funds from numerous cost bearers and the projects are ultimately enjoyed by few beneficiaries.

i would say b. research typically uses a variety of sources