Achain is a sequence of amino acids that is the foundation for the basic structure of a protein.
a. polynomial
b. polypeptide
c. polysaccharide eliminate
d. polyunsaturated

The correct answer is (B) Polypeptide.

When two amino acids are joined, the formation of peptide bond takes place by the loss of a molecule of water.Each of the the amino acid joins to form protein and the bond between them is peptide bond. A series of amino acid joined by peptide bonds forms a polypeptide chain.

which

the earth is thought to have been formed about 4.6 billion years ago by collisions from a cloud of hydrogen, helium, rock, ice and other materials. these were pulled together by gravity to form objects in and around earth like- asteroids and small early planets called planetesimals.

so, the best possible answer to this question will be option d- to harden materials to form different parts of earth’s layers