The correct answer is option A, an asteroid hitting the earth
Reason -
The extinction event of Cretaceous is considered as a mass extinction process in which near about 3/4th of the species on planet earth became extinct. The researches conducted (found in geologic record) to study the cause of this massive extinction event, revealed presence of iridium metal on the Earth crust which is a rare metal and is usually found in the asteroids or comets. Thus, hitting of planet earth by the asteroids or comets can be considered as a cause of this massive extinction.
Karen is NOT correct. This is because the sun's energy is a renewable resource. This means that its use is sustainable hence it is a substance of economic value that can be replaced or replenished in the same or less amount of time as it takes to draw the supply down. Though the sun is a finite resource, it cannot be depleted within human timescale.
