The mass extinctions that occurred 250 million years ago and 65 million years ago may have been due to gradual process or Catastrophic events.
I answer i would choose is C
It is true that an organism that is asymmetrical can not be divided into identical or mirror images.
The tongue has been considered as the strongest muscle yet it is a group of muscles. This is because it does not stop working. It is use if someone is eating, drinking, pushing the food as well as the liquid down to the throat and works to keep saliva out of one's mouth.