There are a total of 20 amino acids that serve as the building blocks of proteins. These amino acids are categorized into essential and non-essential types. The options provided (three, seven, nine, or five) do not accurately represent the total number of amino acids. ;
There are 20 amino acids that serve as the building blocks of proteins. The offered options (three, seven, nine, or five) do not reflect this total. Therefore, none of the listed answers is correct.
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