The correct answer is letter B. Horizontal water movements. Upwelling is a phenomenon that involves the dense's motion because of the wind. It is cooler and makes the water rich in nutrients towards the ocean surface. The warmer air is replaced and nutrient-depleted surface water are also replaced. This makes increase in plankton population and increase in nutrients at the ocean surface. The movement of the water is vertically up.
In a rocket, burning fuel creates a push on the front of the rocket pushing it forward. This creates an equal and opposite push on the exhaust gas backwards
Would weaken the hypothesis beacuse it would show that many droughts indicated in the stalactites do not always show a collapse in society. Societes could therefore cope with droughts.