Question

1. Which layer is MOST responsible for the movement of continents?

A. the outer core
B. the asthenosphere
C. the mantle
D. the continental crust
2. What is the main cause of earthquakes and volcanic eruptions?
A. the melting of oceanic crust
B. the continental crust cracking in a given location
C. collisions between tectonic plates
D. friction between the the mantle and the asthenosphere

Answer 1

"The asthenosphere" is the one layer among the following choices given in the question that is most responsible for the movement of continents. The correct option is option "B".

2. "Collision between tectonic plates" is the main cause of earthquakes and volcanic eruptions. he correct option among all the options given in the question is option "C". 

Answer 2

1. The answer is B. the asthenosphere

Asthenosphere is a layer of the Earth situated below the lithosphere. It is a semi-fluid and ductile rock or partly molten rock. Due to semi-fluid state of asthenospheric rock, it behave like a plastic and flow gradually. Thus, causes movement of continents.  

2. The answer is C. collision between tectonic plates

The Earth’s crust becomes unstable when tectonic plates meet. As the plates slide past each other and push against each other. This causes earthquakes and volcanic eruptions at the edge between the plates.