If tire tread depth is too shallow on wet roads, what risk increases?

• A. Braking and steering performance degrades, increasing stopping distance.
• B. Braking becomes more effective.
• C. Hydroplaning cannot occur.
• D. Tire life increases.

Answer: (A)

On wet roads, tread depth acts like a water channel for the tire. When tread is shallow, it can’t displace water quickly enough, so a layer of water builds between the tire and the road. That reduces traction, making braking less effective and steering less responsive, which leads to a longer stopping distance. The risk also includes a higher chance of hydroplaning as the tire loses contact with the road surface when there's a water film.

So the best answer is that braking and steering performance degrade, increasing stopping distance. The other options don’t fit: braking doesn’t become more effective with reduced tread, hydroplaning can occur (and is more likely) with shallow tread, and tire life isn’t increased by shallower tread.