12. Movement of plate boundaries results to minions or land formations which of the following is the reason of mountain formation?
A. Convergent plates
B. Divergent plated
C. Both A and B
D. None of them

13. Which of the following is associated with the discovery of seafloor spreading?
A. Mountains and volcanoes are denser than mantle
B. Rotational pole of the earth has migrated or moved
C. The crust of the continents is denser than the crust of the ocean
D. The crust of the ocean is very young relative to the age of the crust of the continents

14. Which type of plate boundary does shallow focus earthquake occur wherein it appears to be associated with mid ocean ridges and mountain ranges?
A. Convergent
B. divergent
C. transform
D. all of these

15. When two tectonic plates collide, the continental crust usually rise up over the oceanic crust because it is ____?
A. Denser than the continental crust
B. Thicker than the continental crust
C. Thinner than the continental crust
D. Less denser than the oceanic crust​