The correct answer is (b) China.
China launched the world’s largest carbon trading market in July 2021. The market covers 75% of China’s power sector and is expected to reduce emissions by 1.3 billion tonnes of carbon dioxide annually.
The other options are incorrect.
(a) The U.S.A. does not have a national carbon trading market. However, there are several regional carbon trading markets in the U.S., such as the Regional Greenhouse Gas Initiative (RGGI) and the California Cap-and-Trade Program.
(c) France has a national carbon trading market, but it is much smaller than China’s market.
(d) India does not have a national carbon trading market. However, the government is considering launching one in the future.