When should you reduce your speed while exiting the highway?

• Only after moving into the deceleration lane
  Explanation:

  "When exiting the highway, it is advisable to start reducing speed only after moving into the deceleration lane. This lane is specifically designed to allow drivers to slow down safely without disrupting the flow of traffic on the main highway."
• Immediately upon entering the exit ramp
• Once you reach the highway exit sign
• After completely leaving the highway