https://preparationpoint.info/solved-past-papers-mcqs/ppsc-past-papers/ppsc-past-papers-2018/model-paper-85-assistant-director-bs-17-2018-in-local-government-community-development-department/which-theory-laid-down-that-all-matter-is-composed-of-discrete-units-called/
Which theory laid down that all matter is composed of discrete units called: