It Has Been Proposed That a New,better Approach to Health

It has been proposed that a new,better approach to health care be tested with a small group to evaluate its effectiveness.Which best describes why this cannot be done?

A) Any employment in the project would be only temporary,so it would be difficult to find professionals to staff the program
B) It is challenging to find appropriate sites located in the target area from which to offer the pilot project service
C) No one wants to accept free services if they include being a guinea pig in a research project
D) Offering a service establishes a precedent and a sense of entitlement,so it is difficult to discontinue the program.