Why is the first half-hour of rainfall considered the most dangerous for driving?

• Because the rain clears dust particles in the air, allowing for better visibility
• Because the rainwater mixes with oil on the road surface, making the condition extremely slippery
  Explanation:

  "The first half-hour of rainfall is the most dangerous because roadways become extremely slippery when the water mixes with oil and other chemicals on the road surfaces."
• Because it makes the road surface extremely dry and increases tire grip
• None of the above