ANS:B - metal

In materials science, "metal" refers to a class of chemical elements characterized by their luster, malleability, ductility, and conductivity, among other properties. Metals are typically solid at room temperature (with the exception of mercury) and have high melting and boiling points compared to non-metals. They are typically found on the left side of the periodic table and include elements like iron, copper, aluminum, gold, and silver. Metals are known for their ability to conduct both heat and electricity, making them essential materials in various applications ranging from construction and manufacturing to electronics and transportation. They exhibit metallic bonding, where atoms share their outer electrons freely throughout the material, resulting in a "sea" of delocalized electrons that can move easily in response to an applied electric field, facilitating electrical conductivity. Due to their unique properties, metals are widely used in industries such as aerospace, automotive, infrastructure, and electronics. They can be alloyed with other elements to enhance specific properties, such as strength, corrosion resistance, or electrical conductivity, to suit different applications.