Answer:
A. test the composite drug in a trial run
Explanation:
 
        
             
        
        
        
The answer to this question would be frequency.
The pitch of a sound makes is directly related to the frequency of the vibration. For every octave, the number of frequency will be increased 2 times. The frequency is influenced by various things. Changing the length of the instrument is the easiest method to change the frequency.
        
             
        
        
        
Answer:
The correct answer is - carbohydrates.
Explanation:
The four significant groups of macromolecules found in living beings are carbohydrates, lipids, nucleic acids, and proteins. carbohydrates comprised of carbon, hydrogen, and oxygen molecules, generally in a proportion of 1 : 2 : 1. 
Living things use carbohydrates as their main form of energy.  Carbohydrates are a class of macromolecules is essentially utilized as a quickly accessible energy source by living things.
Thus, the correct answer is - carbohydrates.