Question

a rubber compound that works closely with the beads and bead filler to keep air inside of the tire: cord body sidewall bead filler cord body beads tread belt plies inner liner

Explanation:

To determine the correct component, we analyze each option:

• Sidewall: Protects the tire's side, not for air retention with beads/filler.
• Bead Filler: Fills the bead area, not the main air - retaining rubber with beads.
• Cord Body: Provides structure, not primary air - sealing with beads/filler.
• Beads: Anchor the tire, not the rubber compound working with them for air retention.
• Tread: Contacts the road, not for air retention.
• Belt Plies: Reinforce the tread, not for air retention.
• Inner Liner: Is a rubber compound that works with beads and bead filler to keep air inside the tire.

Answer:

Inner Liner