The correct answer is D) decreased trade with other countries.
The aspect that was not happening in the second half of the 18th century was decreased trade with other countries.
The Industrial Revolution made possible many advances such as new machines in the factories that allowed mass production. This created more jobs and help the manufacture of products that could be exported. Agriculture Revolution was also a consequence of this time. So, trade increased and represented a solid income for industrialized countries. For those reasons, decreased trade with other countries was not happening in the second half of the 18th century.