Answer:
The correct answer for this question is B. Tornadoes. 
Explanation:
Based on the information of the graph and including the things you have learned about severe weather in this unit, the severe weather that is represented by the lines on the graph are tornadoes.
 
        
             
        
        
        
Cells are made of many complex molecules called macromolecules, which include proteins, nucleic acids (RNA and DNA), carbohydrates, and lipids. The macromolecules are a subset of organic molecules (any carbon-containing liquid, solid, or gas) that are especially important for life.