Question

the primary structure of a protein is determined by:
the overall three - dimensional shape formed by a single polypeptide chain.
the unique linear sequence of amino acids linked by peptide bonds.
the interaction and arrangement of multiple polypeptide subunits.

Explanation:

The primary structure of a protein is defined by the linear sequence of amino - acids joined by peptide bonds. The three - dimensional shape of a single polypeptide chain refers to secondary and tertiary structures, and the interaction of multiple polypeptide subunits is the quaternary structure.

Answer:

The unique linear sequence of amino acids linked by peptide bonds.