 Complete the following phrase:  Marita Covarrubias is introduced as an informant to Fox Mulder David Duchovny after the death of his former source, X Steven Williams. X scrawls the letters SRSG in his own blood as he dies, leading Mulder to the Special Representative to the Secretary-General of the United Nations. Covarrubias uses her diplomatic connections to help Mulder infiltrate the Russian province of Krasnoyarsk, allowing him to reach the site of the 