Which field would encompass the study of marine biology?

Marine biology is fundamentally concerned with the study of organisms that inhabit the ocean and other saltwater environments. As an interdisciplinary field, it focuses on various aspects of marine life, including the biology of marine species, their ecosystems, and their interactions with environmental factors.

Oceanography is the most appropriate field in this context because it specifically involves the study of the physical, chemical, biological, and geological properties and processes of the ocean. Within oceanography, marine biology is a crucial component as it examines the biological aspects of ocean ecosystems, looking at the diversity of marine organisms, their behaviors, and roles within these systems.

While physical science, geology, and earth science touch upon some aspects of the marine environment, they do not focus specifically on biological processes or marine life as oceanography does. Physical science primarily studies non-living systems, geology examines the Earth's structure and processes, and earth science broadly addresses various components of the Earth and its atmosphere, but oceanography, in particular, zeroes in on the ocean and its biological intricacies. Therefore, understanding marine life and its interactions within the ocean is best encompassed within the field of oceanography.