1.Scientists found that the continents were moving apart from each other due to magma rising out of mid-ocean ridges, and they called this
A. Underwater volcanos
B. Sea floor spreading
C. Sea floor rising
D. Changing sea floor
2.When the force of gravity pulls a lithospheric plate downward and away from a ridge pushing it toward a trench, what process is involved?
A. Subduction
B. Ridge Push
C. Slab Pull
D. Sea Floor Spreading
3. What is the major driving force that makes the plates to move?
A.subduction
B. slab pull
C. ridge push
D. convection current
4.In a convection current, hot materials move ______________.
A. upward
B. downward
C. any direction
D. sideward
5.The uplifting and tearing apart of lithosphere occurs at ___________________.
A. divergent boundary
B. convergent boundary
C. transform fault boundary
D. mantle
6.A driving force for plate motion at mid-ocean ridges as a result of the rigid lithosphere sliding down _______________.
A. seafloor spreading
B. convection current
C. slab pull
D. ridge push
7.Where is the source of heat in a mantle convection current?
A. the Sun
B. the crust
C. the core
D. the moon
8.Which of the following is NOT a driving force of tectonic plates?
A. ridge push
B. slab push
C. drag force
D. mantle convection
9.How do you describe the rocks as it move farther from the mid-ocean ridge?
A. the rocks become hotter
B. the crust becomes denser.
C. the rocks become younger.
D. the sediment becomes thinner.
10.A convection current is caused by differences in temperature resulting to variation in ___________.
A. density
B. mass
C. air pressure
D. color

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