In which country the first earth summit took place and when ? And what it's objective​

United Nations Conference on Environment and Development (UNCED), byname Earth Summit, conference held at Rio de Janeiro, Brazil (June 3–14, 1992), to reconcile worldwide economic development with protection of the environment.

Explanation:

Earth Summit, conference held at Rio de Janeiro, Brazil (June 3–14, 1992),

and it's objective was to reconcile worldwide economic development with protection of the environment.

the awnser is a

it is not b or c