Why should truck drivers and vehicles pulling trailers leave enough space between themselves and similar vehicles?

• To allow overtaking vehicles to enter and occupy the space safely
  Explanation:

  "When traveling upon a roadway outside a business or residential district, drivers of trucks and vehicles pulling trailers must leave sufficient space between themselves and other vehicles of the same kind, so that the driver of an overtaking vehicle can enter and occupy the space without danger."
• To encourage slower vehicles to drive in their blind spots
• To give motorists enough space to come to a complete stop
• None of the above