D) Industrial processesThe answer is C, volcanic eruptions. While volcanic eruptions can release greenhouse gases and other pollutants into the atmosphere, they are not considered a human activity tha...Chapter 1060: Gas Spirit Pill

The city of Heavenly Sage had been taken over by Taiyuan Mountain. After Huo Feishao was ambushed, the entire city became sealed off only allowing entry but not exit. There were often elders with great power flying over the sky, looking for suspicious people. They would definitely not find anything as they had no clues. Family has always considered themselves to be an extremely dignified existence, one of the earliest humans created by the Heavenly Dao and the supreme ruler among mortals. Hence, they hold all other...