The answer is in the attachment
One astronomical unit is equal to the distance from Earth to the Sun. The second option among all the options given in the question is the correct option. The distance as calculated in the year 2012 by the International Astronomical Union was equal to 149597870700 meters. Astronomers like to use this unit for measuring the distances between planets and other solar bodies.
The correct answer is - Seafloor spreading at the mid-ocean ridge provides the mechanism for tectonic plate movement.
Harry Hess is one of the people that is most important when it comes to the proving and world wide acceptance of the continental drift theory.
Hess was very interested in the topic, and he was constantly looking for clues that would bring light to it and finally have a definite proof of it. While sailing through the Atlantic and doing some examinations, Hess noticed that there high mountains in the water, having flat peaks, and being arranged in an interesting manner. These underwater mountains, named guyouts, were the highest at a certain point, and than on both sides, as the distance was increasing they were becoming smaller and smaller.
What Hess stumbled upon was the seafloor spreading and how it works, and he recognized that quickly. He immediately went on to share what he discovered, that there's magma coming from bellow, solidifying and spreading, thus creating new crust while pushing the old crust away from the center, which is the reason why the continents are moving.
Answer: Dormancy
The phenomenon wherein the leaves of the plants turn red and fall during the autumn season followed by the defoliation of trees is a concrete example of dormancy. Dormancy refers to the time wherein plants don't grow and wait for necessary environmental factors like moisture, temperature and others.