The primary structure of a protein refers to the sequence of amino acids that
are linked together in a long chain. Which of the following common items
would best represent the primary structure of a protein?
A. Beads of different colors joined together on a piece of string
B. A dry kitchen sponge sitting beneath a mound of table salt
C. Two unsharpened pencils held together by a piece of tape
D. A burning wax candle placed in front of a small fan