Step 1: Understanding the question.
The question asks about the host country of the Asian Games held in 2023. Step 2: Analyzing the options. (A) Japan: Japan hosted earlier editions, not 2023. (B) South Korea: Hosted in previous years, not 2023. (C) China: Correct — China hosted the Asian Games 2023 in Hangzhou. (D) Indonesia: Hosted the 2018 Asian Games. Step 3: Conclusion.
The Asian Games 2023 were hosted by China.