Final answer:
Adopting a lower riding position has the greatest potential for reducing aerodynamic drag in cycling, more so than changes to equipment or clothing. (option c)
Step-by-step explanation:
The greatest potential reduction in aerodynamic drag during a cycling competition would be adopting a lower riding position. This decreases the frontal area exposed to the wind and can have a more profound impact on drag than material changes to the bike or clothing. While components like an aerodynamic frame or disc wheels can reduce drag, body position tends to have a larger effect because the rider's body creates the most drag. Also, wearing Lycra shorts and jerseys does reduce drag over baggy clothing but not as much as a riding position change.
When it comes to reducing the mass of a bike, the greatest benefit is seen when reducing the mass of the tires and wheel rims. This is because wheels contribute to the rotational inertia of the bike. If they are lighter, they require less energy to accelerate which allows a racer to achieve greater accelerations than an identical reduction in the mass of the bicycle's frame.
Reducing the rolling resistance by using smoother tires or optimizing tire pressure can also contribute to a decrease in aerodynamic drag. Reducing drag through these methods is similar to how aerodynamic shaping in cars can improve gas mileage by lessening the resistance to the car's movement through the air.