________ nation has refused to join WHO-led international efforts to develop and distribute the COVID-19 vaccine ?

a) China
b) Russia
c) US
d) None of these

The United States said on September 1, 2020 that it will not work with an international cooperative effort to develop, manufacture and equally distribute COVID-19 Vaccine. The Trump Administration stated that it does not want to be constrained by multilateral groups like the World Health Organization.