Which of the following statements is NOT true about roundabouts?

• They improve traffic flow.
• They tend to slow vehicle speed.
• They allow traffic to travel only in a counter-clockwise direction.
• They have traffic signals that help reduce traffic crashes.
  Explanation:

  "The statement "They have traffic signals that help reduce traffic crashes" is NOT true about roundabouts. Roundabouts typically do not have traffic signals; instead, they use yield signs and the circular flow of traffic to manage vehicle movement."