Answer:
b. individual land masses that are moving towards the poles
Step-by-step explanation:
The Mesozoic started with the Triassic period, 251.9 million years ago, after a mass extinction that wiped out most of life on Earth. At this moment, all the continents were part of a continuous landmass called Pangaea. By the Late Jurassic, the continents started to drift towards the poles. Africa and South America stay move from the southern hemisfere towards the Equator, Antartica and Australia move towards the south pole. It is during this time that we have two continents: Laurasia in the north, comprised of Europe, North America, Russia, China, and parts of Central Asia; and Gondwana, comprised of South America, Africa, Australia, India and Antarctica.
Towards the end of the Mesozoic, Laurasia and Gondwana also start to split. Laurasia breaks up and still occupies the Northern hemisphere, but pieces of broken Gondwana drifted north, such as South America, Africa and India. Of these, Africa collided with Europe and originated the Italian peninsula, the Iberian peninsula, and the Balkan region. The collision of India with China, Tibet and Russia prompted the beginning of the formation of the Himalaya.
By the beginning of the Cenozoic, Laurasia and Gondwana had split into several individual landmasses, most of them in the Northern Hemisphere.