Transport technology (tyres): Identify what J. B. Dunlop invented. Full question: What did J. B. (John Boyd) Dunlop invent that revolutionized cycling and later motoring? Choose the correct option.

Background

• Inventor: John Boyd Dunlop (Scotland/Ireland).
• Era: Late 1880s.

Reasoning
Dunlop invented and patented the pneumatic tyre for his son's tricycle in 1888, greatly improving ride comfort and performance. The concept was later applied widely to bicycles and automobiles.

Distractors
Radial tyres — 20th-century Michelin innovation; ball bearings and brakes are unrelated to Dunlop's specific invention.

Final Answer
The pneumatic (inflatable) tyre.