I believe the correct answer is upwelling. Lets say we have producers such as plankton. well upwelling currents bring dead matter from the ocean floor up to the surface, creating plankton.
I believe Mechanical Force is the force you are looking for
I believe the answer is B
<span>A. The nebula contracts and shrinks instead of expanding
</span><span>Nebula is the cloud of interstellar dust and gas that forms a star. It is collborately shaped during colliding and collapsing of the interstellar mediums this is influenced by the gravitational attraction of the atoms and particles in the entites. Hence, there are three types of nebular namely, are classical nebula, diffuse nebula, planetary nebular and supernova remnants.</span>
