Answer:
Convection currents generated within the asthenosphere push magma upward through volcanic vents and spreading centres to create new crust.
OK so when I did this the answer was a and I got it right
The process is called Exfoliation.
Here are some of the achievements of the Tang and Song Dynasties:
1. <span>Literature and arts influenced cultural diffusion between China, Japan, and Korea. This lead to ink painting
2. </span><span>Sailing and ocean trade lead to the invention of the compass and cultural diffusion
3. T</span><span>hey cultivated a lot of rice
4. </span><span>They had a bureaucracy , where people have a say
5. They made many long roads</span>
Establishment of new schools and colleges.
Boost of morale.
Political unification of India.
Growth of nationalism.