How should you check for blind spots while driving on a multi-lane roadway?

To effectively check for blind spots while driving on a multi-lane roadway, it is important to look over your shoulder in addition to using your mirrors. Blind spots are areas around your vehicle that cannot be seen in your mirrors, making it crucial to physically turn your head to ensure there are no vehicles or obstacles present before changing lanes or merging.

Using just mirrors can give a limited view of your surroundings, and relying solely on them may lead to missing vital information about vehicles in adjacent lanes. Honking your horn is not an appropriate method for checking blind spots; it may be used to alert other drivers but does not assist in identifying what is in your blind spots. Slowing down could impact your ability to see any obstacles if other vehicles are present at higher speeds around you; it does not actively help in checking blind spots. Thus, the process of checking blind spots effectively requires a combination of head movement and mirror usage, making none of the provided answers suitable for the correct method.