After a volcanic eruption, lava flowed over an area and then cooled to form a thick layer of new rock. One thousand years later, a thriving forest with diverse flora and fauna is found in that area, even though evidence suggests that several large forest fires have occurred. Which statement best describes what happened?

A.) Secondary succession occurred, followed by several primary successions.
B.) Only secondary successions occurred.
C.) Primary succession occurred, followed by several secondary successions.
D.) Only primary successions occurred

explanation:

the fossil record extends back to a dog-like ancestor some 55 million years ago, which gave rise to the first horse-like species 55 to 42 million years ago in the genus eohippus.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.

a = executive branch; b = judicial branch