You have been using a wireless router at home. you get an e-mail from the manufacturer that the same router now has been provided with new functionality in its admin interface. you want to get this functionality on the same router without losing existing configuration. what should you do with minimum administrative effort? (a) upgrade the firmware on the wireless router(b) visit the manufacturer's service center and request for the upgrade to the router's operating system(c) download the new admin interface and install(d) purchase a new wireless router