Answer:
The correct answer is a. sugar
Explanation:
Even though caffeine is also known for uprising the energy levels to a point where it could cause insomnia, the excess of sugar usually causes an increase in heart rate and insomnia. Also, coca-cola has a bigger amount of sugar than caffeine, so it explains how these high quantities could affect Xi's health. 
 
        
             
        
        
        
Absorbing prokaryotic cells. This theory is called the endosymbiotic theory.
The early prokaryotic cells that were absorbed likely evolved into mitochondria and chloroplasts, membrane-bound organelles with their own DNA in single chromosomes and their own ribosomes.
        
             
        
        
        
The term aerobic exercise describes any type of exercise typically performed at moderate levels of intensity for extended periods of time that increases the heart rate. In such exercise, oxygen is used to "burn" fats and glucose in order to produce energy in the form of ATP, the basic energy carrier for all cells. Initially, glycogen is broken down to produce glucose, but in its absence, fat metabolism is initiated instead. Aerobic exercise is an exercise performed at a moderately high level of intensity over a long period of time. For example, running a long distance at a moderate pace. 
        
             
        
        
        
- - The cell cycle consists of two main phases: interphase and M phase