which of the following is not one of the reasons it is difficult to determine whether a business practice is sustainable or unsustainable?a. unsustainabe levels of productions could be positive in the short term and negative in the long termb. business owners have a clear incentive to only use practices that take into consideration long term consequencesc. the costs and benefit of policy accrue diferent stakeholdersd. we cannot objectively say whether a policy is negative or positive