Identify that water is a compound common to all living things recognize the importance of hydrogen bonding to the properties of water explain why many compounds dissolve in water

Because water molecules are polar(partially negative and postive charge)

The answer is organic matter sinking from the photic zone. The regions are called aphotic because the sun rays cannot penetrate to the depths hence no producers (photosynthetic organisms) can thrive in the regions. Therefore only scavengers, decomposers , and detritivores.