the primary structure of a protein refers to the sequence of amino acids that are linked together in a long chain which oft he following common items would best represent the primary structure of a protein?

there is not 1 highest source of protein, but there are many; meats, fish, poultry, seafood, cheese, eggs, yogurt and milk. the only non complete animal food that is beneficial is gelatin.

sorry if this did not , have a great day!

i think the answer is a.keratin is the pigment responsible for skin color.