Write the letters of the correct answers on the lines at left.

3. Oliver builds a circuit connecting a light bulb to a battery with wires, leaving a gap in one of the wires. He places several objects across the gap to close the loop. He wants to see which objects allow electricity to flow and turn on the light bulb. Why do some materials allow electricity to flow through while others do not?

A. Electricity will flow if the atoms in the material are bound tightly to each other.
B. Electricity will flow if the atoms in the material are bound loosely to each other.
C. Electricity will flow if the electrons are bound tightly to their atoms in the material.
D. Electricity will flow if the electrons are bound loosely to their atoms in the material.