Question: The main battle tank that Centurion ARV Mk II was based on was used introduced in what year?

Context paragraphs:
Centurion (tank): The Centurion was the primary British main battle tank of the post-Second World War period.  Introduced in 1945, it is widely considered to be one of the most successful post-war tank designs, remaining in production into the 1960s, and seeing combat in the front lines into the 1980s.  The chassis was also adapted for several other roles, and these have remained in service to this day.

Ford GT40: The Ford GT40 is a high-performance endurance racing car based on the British Lola Mk6, with the Mk I, Mk II, and Mk III designed and built in England and the Mk IV built in the United States.  The range was powered by a series of American-built engines modified for racing.  The GT40 won the 24 Hours of Le Mans four consecutive times, from 1966 to 1969 (1966 being the Mk II, 1967 the Mk IV, and 1968-1969 the oldest chassis design, the Mk I), including a 1-2-3 finish in 1966.  In 1966, with Henry Ford II himself in attendance at Le Mans, the Mk II GT40 provided Ford with the first overall Le Mans victory for an American manufacturer, and the first victory for an American manufacturer at a major European race since Jimmy Murphy´s triumph with Duesenberg at the 1921 French Grand Prix.  The Mk IV GT40 that won Le Mans in 1967 is the only car designed and built entirely in the United States to achieve the overall win at Le Mans.

Type 99 tank: The Type 99 () or ZTZ99 is a Chinese third generation main battle tank (MBT).  The vehicle was a replacement for the aging Type 88 introduced in the late 1980s.  The Type 99 MBT was China's first mass-produced third generation main battle tank.

Leopard 2: The Leopard 2 is a main battle tank developed by Krauss-Maffei in the 1970s for the West German Army.  The tank first entered service in 1979 and succeeded the earlier Leopard 1 as the main battle tank of the German Army.  Various versions have served in the armed forces of Germany and 12 other European countries, as well as several non-European nations, including Canada (Leopard 2A4m can), Chile, Indonesia, Singapore and Turkey.  The Leopard 2 was used in Kosovo with the German Army and has also seen action in Afghanistan with the Danish and Canadian contributions to the International Security Assistance Force, as well as seeing action in Syria with the Turkish Armed Forces against IS and the YPJ.

TR-85: The TR-85 is a main battle tank designed for the armed forces of Romania.  Based on the TR-77-580 (Romanian-built version of the Soviet T-55 tank), the TR-85 tank was developed from 1978 to 1985 and produced from 1986 until 1990.  A modernization program was initiated in March 1994 in order to upgrade the TR-85 tanks to NATO standards.  The result was the TR-85M1 main battle tank, currently the most modern tank in service with the Romanian Land Forces.  Although a further development of the T-55, the TR-85M1 uses a T-block powerpack (similar to the one used in the Leopard 1) based on a V8 German 830 hp diesel engine, an improved turret, a locally-designed "Ciclop" fire control system (with cross-wind sensor, laser rangefinder and night vision), new 100 mm BM-412 Sg APFSDS-T projectiles and a completely redesigned suspension with 6 road wheels on each side, protected by metal side skirts.  Combat weight is 50 tons.

Centurion ARV Mk II: The Centurion ARV Mk II, was a British armored recovery vehicle based on the Centurion main battle tank.

CM-11 Brave Tiger: The CM-11 Brave Tiger (勇虎式戰車) is a Main Battle Tank (MBT) that was developed by the American General Dynamics and the Republic of China Army (ROCA) Armored Vehicle Development Center It was introduced to the public on 14 April 1990.  Being a variant of the M48 Patton, it is also known as the M48H Main Battle Tank.  The Ministry of National Defence is now acquiring the M1A1 Abrams to supplement the CM-11.

VT-4: The VT4 main battle tank ( ), also known as the MBT3000, is a Chinese third generation main battle tank built by Norinco for overseas export.  It is an upgraded variant of the MBT2000 (VT-1) and the latest tank model from the Type 90-II tank family.

Chieftain (tank): The FV4201 Chieftain was the main battle tank of the United Kingdom during the 1960s, 1970s and 1980s.  It was the "most formidable main battle tank in the world" at the time of its introduction in 1966 with the most powerful main gun and most effective armour of any tank yet made.  .  This was further improved while in service with Chobham armour upgrades.

Stingray light tank: The Stingray is a light tank produced by Textron Marine & Land Systems division (formerly Cadillac Gage).  It was specifically designed to use as many existing components of other American armored fighting vehicles as possible to keep costs down.  It was originally developed for the U.S. Army as a light tank—with firepower matching that of a main battle tank (MBT), while lacking the countermeasures to be considered a main battle tank—for the U.S. Army's Armored Gun System competition in the 1980s.  It was exported for use by armed forces of Thailand, who remains the only user.

Supporting paragraphs: Centurion ARV Mk II Centurion (tank)
Answer: 1945