Some of the requisite documents include original policy document, counter signed claim form, address proof of the nominee, copy of death certificate issued by local authority, etc.. (policybazaar.com)
This follows the decline in certificates issued in previous years. (newlawjournal.co.uk)
You can also see if a root certificate is trusted by opening it and running a search on the name of certificate issuing authority. (thewindowsclub.com)