Which Of The Next Is The Right Format For A Custom Crusade Parameter Added To A Url?

Which of the next is the right format for a custom movement parameter added to a URL?
(select all that apply)


www.googlemerchandisestore.com/?utm campaign=fallsale

www.googlemerchandisestore.com/?utm_campaign=fallsale

www.googlemerchandisestore.com/?utm_campaign=fall_sale


www.googlemerchandisestore.com/?utm_campaign = autumn sale