Answer: the correct option is : highly developed cell- cell communication.
Explanation: In complex multicellular organisms, cell - cell communication also known as cell signalling is part of any communication process that leads basic activities of cells and coordinates multiple cell functions.
 
        
             
        
        
        
A landform is a natural feature of the solid surface of the Earth or other planetary body. Landforms together make up a given terrain, and their arrangement in the landscape is known as topography. Typical landforms include hills, mountains, plateaus, canyons, and valleys, ... Oceans and continents exemplify the highest-order landforms.
 
        
             
        
        
        
Answer: D
Explanation:
The lipopolysaccharides are found in the outer membrane of Gram-negative bacteria. Lipopolysaccharide is complex molecule consisting of a lipid and chains of carbohydrates. They are also called endotoxin, they are the major component of the outer cell membrane. Sugars in the polysaccharide chains of endotoxin confer serologic specificity. They lplay a crucial role in bacteria resistance to antibiotics.
 
        
             
        
        
        
Nucleus for what?
Atom? Animal Cell? Plant Cell? Each have different structures.