Which of the following describes the study of substances and processes occurring in living things?

The study of substances and processes occurring in living organisms is specifically referred to as biochemistry. This field combines principles of both biology and chemistry to understand the molecular mechanisms that underlie cellular processes, including the structure and function of biomolecules such as proteins, nucleic acids, carbohydrates, and lipids. Biochemistry focuses on how these molecules interact, how metabolic pathways operate, and how energy is transferred within cells, thereby revealing the biochemical foundations of life.

While biology is the overarching science that encompasses the study of all living organisms and their interactions, it is broader and includes many sub-disciplines, including biochemistry itself. The other terms, such as physics, deal with laws of nature and matter but do not focus specifically on living systems. Microbiology studies microorganisms and their effects, which is also a specialized area within biology rather than a direct examination of the substances and processes across all living things as biochemistry does.