In Terms of an Economic Contribution, Building a Football Stadium

In terms of an economic contribution, building a football stadium

A) to attract a team has always been a successful strategy in growing an community's economy.
B) to keep a team that would otherwise leave has always been a successful strategy in growing an community's economy.
C) with public dollars has never been shown to enhance a community's economy.
D) has been shown to be futile. The team leaves anyway.