What is the goal of a sustainable environment?
a. the people use natural resources without concerns about physical environment inequalities.
b. the physical environment is able to meet the needs of people.
c. the government is able to prevent wars that destroy physical environments.
d. the social institutions are able to control the desire of people to purify the environment.

The definition of a sustainable environment is an environment that can simultaneously meet the needs of the ones living in the environment without damaging it. Therefore, B would be incorrect because there is no concern for the environment's safety. C would also not make sense because it implies that there will be damage to the environment. D also does not make sense because there is nothing concerning the equilibrium between those who exist in the environment and the environment. Therefore A should be your best answer by choice.