Answer
**B. Changes in ocean currents
details
Plate tectonics significantly influences the Earth's climate by rearranging the continents and oceans. This rearrangement affects ocean currents and atmospheric circulation patterns, which in turn impact global temperatures and climate systems.
Here's how the given options relate to the impact of plate tectonics during the Cenozoic era:
**A. Changes in atmospheric winds** - While this is true, the changes in atmospheric winds are more a result of the changes in ocean currents and continental positions than a direct result of plate tectonics.
**B. Changes in ocean currents** - This is the most direct effect of plate tectonics on global temperatures. The movement of tectonic plates has altered the positions of continents and the shape and size of oceans, which affects ocean currents. Ocean currents play a crucial role in regulating the Earth's climate by distributing heat around the planet. For example, the formation of the Isthmus of Panama blocked ocean currents between the Atlantic and Pacific Oceans, which significantly impacted global climate patterns, leading to glaciation and cooler global temperatures.
**C. Cooler landmasses** - While the movement of continents into different climatic zones (like near the poles) can lead to cooler landmass temperatures, this option is more of a consequence of the positions rather than a direct effect of plate tectonics affecting global temperature.
**D. Increases in biodiversity** - This is also true in the broader ecological impacts of plate tectonics, as the creation of new habitats and isolation of landmasses can lead to speciation and increased biodiversity. However, it does not directly relate to changes in global temperature.
Considering the direct connection to global temperature changes, the best choice is:
**B. Changes in ocean currents**
This option directly links to how plate tectonics can affect global temperatures during the Cenozoic era through alterations in oceanic circulation patterns, which are critical in controlling the Earth's climate system.