Answer – B (Electrons)
When atoms combine, their nucleons fuse to produce a new nucleus and interactions occur between their electrons, particularly the outer valence electrons. The interaction between the outer valence electrons of the combining atoms forms bonds between them.
        
             
        
        
        
Answer: Medication can be tested on the cancer culture before being injected into the patient.
 
        
             
        
        
        
B. they are single molecules...
        
             
        
        
        
Answer:
regional metamorphism is a metamorphism that is affecting rocks over an extensive area as a result of the large-scale action of heat and pressure.
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