Oceanography is a diverse field of study that encompasses biology, chemistry, geology, and physics. As a result, it can be broken down into several areas of expertise. One area is physical oceanography. A physical oceanographer studies the ocean's physical attributes and processes. In contrast, a geological oceanographer concentrates on the landforms on the seafloor, such as mountains and valleys. A biological oceanographer studies the ocean as a complex ecosystem. This type of scientist is interested in the interactions among various populations of marine life. A fourth type of oceanographer is a chemical oceanographer. He or she studies the chemical components of ocean water. This can include an examination of the ways that seawater chemically interacts with both the atmosphere and the ocean floor. Which example, if added to the blank, would best help to develop the topic? 1. This kind of expertise demands a deep understanding of the sea. 2. A physical oceanographer might study the Atlantic and Pacific Oceans. O 3. Erosion is a physical process an oceanographer would most likely find interesting. 4. This area requires knowledge of waves, tides, and currents, as well as the movement of sand.