Information:  - The Soviet Union, officially the Union of Soviet Socialist Republics (USSR " ) was a socialist state in Eurasia that existed from 1922 to 1991. A union of multiple subnational republics, its government and economy were highly centralized. The Soviet Union was a one-party federation, governed by the Communist Party with Moscow as its capital.  - Harold Adrian Russell "Kim" Philby (1 January 1912  11 May 1988) was a high-ranking member of British intelligence who worked as a double agent before defecting to the Soviet Union in 1963. He served as both an NKVD and KGB operative.  - In the field of counterintelligence, a double agent (also double secret agent) is an employee of a secret intelligence service, whose primary purpose is to spy on a different target organization, but who, in fact, is a member of the target organization.  - Colonel Valentine Patrick Terrell Vivian CMG CBE ( 1886 -- 1969 ) was the vice-chief of the SIS or MI6 and was the first head of its counter-espionage unit , Section V. It was Vivian , who while attempting to introduce new blood into the service , selected Kim Philby who was later to become notorious as `` The Third Man '' double agent and who defected to the Russians causing considerable harm to the system he had infiltrated .  - The KGB, an initialism for "Komitet gosudarstvennoy bezopasnosti" (translated in English as Committee for State Security), was the main security agency for the Soviet Union from 1954 until its break-up in 1991. Formed in 1954, as a direct successor of such preceding agencies as the Cheka, NKGB, and MGB, the committee was attached to the Council of Ministers. It was the chief government agency of "union-republican jurisdiction", acting as internal security, intelligence, and secret police. Similar agencies were constituted in each of the republics of the Soviet Union aside from Russia and consisted of many ministries, state committees, and state commissions.    Given the information above, choose from the list below the object entity that exhibits the relation 'employer' with the subject 'valentine vivian'.  Choices: - capital  - cheka  - kgb  - nkvd  - secret intelligence service
The answer to this question is:
secret intelligence service