If this were the case that magma would harden into rock therefore creating new crust
Answer:
Cyanobacteria are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food. Because they are bacteria, they are quite small and usually unicellular, though they often grow in colonies large enough to see. They have the distinction of being the oldest known fossils, more than 3.5 billion years old, in fact! It may surprise you then to know that the cyanobacteria are still around; they are one of the largest and most important groups of bacteria on earth.
The answer to the question stated above is letter b. <span> <span>a meteor or asteroid colliding with Earth
</span></span> <span>The mass extinction at the end of the Mesozoic Era was caused by </span>a meteor or asteroid colliding with Earth. This was said to happen about 65 million years ago.