(b) ductility
The ability of metals to be drawn into thin wires is called ductility.
Source: Chapter 3, Section 3.1.1
The question tests knowledge of physical properties of metals. "Malleability" refers to being beaten into thin sheets, not wires. "Ductility" is specifically defined in the textbook as the property of being drawn into thin wires. Examiners expect the exact term as stated in the NCERT text.