Answer: C. Gravel
Gravel has the highest permeability.
Description
Newton's law of universal gravitation is usually stated that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Water means it is the mixture of hydrogen and oxygen. As we know that
hydrogen is colourless as well as oxygen is also colourless gas.
So at last when hydrogen and oxygen reacts with one another and they
form H2O means water. If both are colourless so their product will also
be colourless. So water is seen colourless.
Blood carries immune system cells, known as white cells or leukocytes. Some examples of white cells are phagocytes and lymphocytes.
Phagocytes ingest and dissolve pathogens, as well as strange particles or dying cells.
Lymphocytes are divided into T cells, B cells, and natural killer cells (NK). B cells produce antibodies to respond to foreign cells, T cells attack pathogens using enzymes and other non-antibodies responses, while NK cells combat tumors and cells infected by viruses.