Answer:
A. They are constantly moving. I think.
Explanation:
Each lithospheric plate is composed of a layer of oceanic crust or continental crust superficial to an outer layer of the mantle. Containing both crust and the upper region of the mantle, lithospheric plates are generally considered to be approximately 60 mi (100 km) thick. Earth's tectonic plates may have taken as long as 1 billion years to form, researchers report today in Nature. The plates — interlocking slabs of crust that float on Earth's viscous upper mantle — were created by a process similar to the subduction seen today when one plate dives below another, the report says. A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Plate size can vary greatly, from a few hundred to thousands of kilometers across; the Pacific and Antarctic Plates are among the largest.
 
        
             
        
        
        
I believe you're looking for "chemical digestion".
Chemical digestions is where food that we ate is digested into simpler and soluble molecules that can be absorbed by our body. Enzymes are used as a catalyst to speed up the reaction.
One example is the digestion of lipids. Enzyme named lipase is used to speed up the digestion of lipids into 3 fatty acid molecules and 1 glycerol. This way, our body can absorb these simple molecules, and use them in order to make our body function.
On the other hand, physical digestion does not include enzymes, such as chewing in our mouth, therefore, don't mix them up!
        
             
        
        
        
Red blood cells is the Andes