Metals can be stretched into wires because they are

Step 1: Analyze the question The question asks which property lets metals be stretched into wires.

Step 2: Explain the concept Several physical properties of metals are easy to mix up:

• Ductility is the ability of a metal to be drawn or stretched into thin wires.
• Malleability is the ability of a metal to be hammered or rolled into thin sheets without breaking.
• Conductivity is the ability to allow heat or electricity to pass through.
• Lustre is the shiny appearance of a metal surface.

These properties are possible because metallic bonding involves positive ions surrounded by a "sea" of delocalised electrons. When a force is applied, layers of ions slide over one another, and the electron sea keeps holding them together. The metal changes shape without breaking.

Step 3: Apply it to the options

• A. Ductile: matches "stretched into wires".
• B. Good conductors: this is about electricity and heat, not stretching.
• C. Lustrous: this is about shininess.
• D. Malleable: this is about sheets by hammering, not wires.

Step 4: Answer The correct option is A. Ductile.

Tip: Link Ductile with Drawing into wires, and Malleable with Moulding or hammering into sheets. Examples are copper wires (ductile) and aluminium foil (malleable).