Which statement properly describes the plate tectonics theory? a. Continents move above the ocean floor. b. Ocean waters seep through the continents, breaking them apart. c. Volcanic eruptions strongly jostle the ground, causing the continents to separate. d. Fragments of lithosphere carry the continents and ocean basins as they move above the asthenosphere.
The correct answer and explanation is:
Correct Answer: d. Fragments of lithosphere carry the continents and ocean basins as they move above the asthenosphere.
Explanation (300 words):
The Plate Tectonics Theory is a unifying scientific concept that explains the structure and movement of Earth’s outer shell, the lithosphere. According to this theory, the lithosphere is divided into large slabs called tectonic plates, which float and move on a softer, more fluid layer of the mantle called the asthenosphere.
These plates include both continental crust (which makes up landmasses) and oceanic crust (which lies beneath oceans). They are not stationary. Instead, they are constantly in motion due to convection currents in the underlying asthenosphere, which are driven by heat from Earth’s core. As these plates move, they interact at boundaries in different ways—colliding, sliding past one another, or pulling apart—leading to geological phenomena such as earthquakes, volcanic activity, mountain building, and the creation of ocean trenches.
Option (a) is incorrect because continents do not float independently above the ocean floor; they are part of tectonic plates.
Option (b) is scientifically inaccurate. Ocean water does not seep into continents to break them apart.
Option (c) wrongly attributes plate movement to volcanic eruptions. While volcanic activity results from plate movement, it does not cause the plates themselves to move.
Option (d) correctly describes the essence of plate tectonics. The continents and ocean basins are part of lithospheric plates, and these plates move atop the asthenosphere. This movement has shaped Earth’s surface over millions of years and continues to do so today.
In short, plate tectonics explains continental drift, seafloor spreading, and many geological features and events. It is one of the most important frameworks for understanding Earth’s dynamic nature.