The figure shows a router advertisement message being sent by a router in response to a router solicitation message.  The router advertisement in the figure is using option two and it is telling the computer the prefix, prefix-length, and the default gateway to use.  It is also using Stateless Address Auto-configuration and tells the computer that a DHCPv6 server is needed for DNS information.  The computer then sends out a DHCPv6 solicit request looking for DNS information.