Explanation:
A high molecular weight compound formed by combining large numbers of small molecules of low molecular weight is called Polymer.A polymer is a large molecule composed of many repeated sub units, known as monomers. Because of their broad range of properties, both synthetic and natural polymers play an essential and ubiquitous role in everyday life.Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins, that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via the polymerisation of many monomers.Their large molecular mass relative to small molecular compounds produces unique physical properties, including toughness, viscoelasticity and a tendency to form glasses and semicrystalline structures rather than crystals.Hence, the correct option is (A).