Step-by-step explanation:
Amino acids are molecules formed by a carboxyl group and an amine group that bond to a carbon atom. Also attached to this carbon are a hydrogen atom and a radical that varies according to the amino acid and is usually called the R group.
The term peptide refers to the joining of two or more amino acids through peptide bonds, which occur between the carboxyl group of one amino acid and the amine group of another. When these groups bond, water is formed (dehydration reaction) due to the loss of a hydroxyl from the carboxyl group and a hydrogen from the group.
Peptides differ from each other by the number of amino acids and the sequence of these molecules. According to the number of amino acids they have, we can classify them into dipeptides, when they are formed by two amino acids; tripeptides, when they are formed by three; tetrapeptides, when they are made up of four amino acids, and so on. When we have several amino acids linked together, we use the name polypeptide.
Answer: A. Polypeptide.