Spoiler Mr B can step down just where he is starting and then he can dropdown ball by his head to end point. This is a loop hole/shortcut. No need to walk on whole path.
@Sunil Kargwal can you please put your comment into a Spoiler section (with the + button of the editor toolbar)?, so you don't break user experience to other players that try the level. Thanks! By the way, great shortcut.