Answer : The correct option is, It connects amino acids.
Explanation :
Protein : It is formed by assembling of amino acid which considered as the building block of proteins. It means that is made up of linkage of two or more amino acid and the two amino acid linked by a bond, known as peptide bond.
A peptide bond is a type of covalent bond which is formed between the carboxylic group
of one amino acids and amine group
of another amino acid.
Hence, the purpose of the peptide bond is that it connects amino acids.